Biomedical subjects

B C Cho

Publications and source records attributed to B C Cho.

At least 19 recordsLinked to original sources

PubMed2001

Distraction osteogenesis after membranous bone onlay grafting in a dog model.

PURPOSE: The purpose of this experiment was to study the possibility of distraction osteogenesis in a membranous bone onlay graft to the mandible and to clarify the histology of the bone repair. MATERIALS AND METHODS: Four dogs, 5 months of age at the beginning of the experiment, were used for this study. The zygomatic arch was exposed in the subperiosteal plane, and a 3-cm long, full-thickness portion of the arch was harvested. The lateral surface of the mandibular body was exposed in the subperiosteal plane, and the bone was fixed to the lateral surface as a membranous onlay graft using screws. A vertical osteotomy through the graft and underlying mandibular body was done postoperatively at week 1 in dog 1, week 2 in dog 2, week 3 in dog 3, and week 4 in dog 4. An external distraction device was applied to the mandibular body, and distraction was started 7 days after the operation at a rate of 1 mm/d for 10 days. After completion of distraction, the device was left in place for 6 weeks to allow for bony consolidation. Radiographs were carried out at 2, 4, and 6 weeks postdistraction. All dogs were killed 6 weeks after distraction. RESULTS: New bone between the native underlying mandibular segments was generated in the distraction zone in all dogs. New bone was not generated between the segments of the membranous bone onlay graft in dog 1, but was generated in dog 2, dog 3, and dog 4. However, in dogs 2 and 3, the new bone between the segments was less firm, with more fibrous tissue, than the bone between the native underlying mandibular segments. Histologically, the distraction gap between the segments of the membranous bone onlay graft in dogs 2 and 3 was composed of considerable fibrous tissue in the central zone and activated osteoblastic cells forming new bone in the margins. In dog 4, there was much more osteoblastic activity in the distraction gap, and the new bone had the appearance of almost normal cortical bone. CONCLUSION: These findings show that distraction osteogenesis is possible in a membranous bone onlay graft and suggest that the distraction should be performed at least 4 weeks after the onlay grafting.

Animals↗

PubMed2001

Bimaxillary osteodistraction for the treatment of facial asymmetry in adults.

Nine patients with hemifacial microsomia or facial asymmetry were treated between April 1998 and November 1999. The ages of the patients ranged from 21 years to 45 years (mean: 24.6 years); six were female and three were male. The follow-up period ranged from 6 months to 24 months (mean: 15.3 months). The operative procedure was based on Ortiz Monasterio's simultaneous mandibular and maxillary distraction technique. This technique frees only the pterygo-maxillary junction of the affected side, thereby leaving the nasal septum and the pterygo-maxillary junction of the unaffected side intact. It also uses an external corticotomy on the mandible. In contrast, we modified Ortiz Monasterio's method by using a complete LeFort I osteotomy with both a complete separation of the pterygo-maxillary junction and a mandibular osteotomy to avoid any resistance during distraction. In one patient with scleroderma and severe atrophy of the mandible and soft tissue on the right side of the face, a free scapular osteocutaneous flap was used; 1 month later we performed simultaneous distraction of the maxilla and transfer of the scapula bone to the mandible. In one patient with hypoplasia of the zygoma, zygoma expansion was also performed simultaneously. Bidirectional distraction was performed in one patient and intraoral devices were applied in three patients. After a latent period of 5 days, distraction was performed at a rate of 1 mm per day. After a consolidation period of 6-8 weeks, the intermaxillary fixation and distraction devices were removed. Preoperatively, the deviation of the occlusal plane ranged from 8degrees to 13 degrees (mean: 10.5 degrees); the distraction distance ranged from 7 mm to 17 mm (mean: 13 mm). In two patients there was radiologic evidence of relapse 6 months after distraction, but no significant change in facial appearance was observed. Seven patients maintained a stable preoperative occlusal relationship and the preoperative lateral open bite was improved postoperatively in two patients. The postoperative occlusal plane was between 0 degrees and 1 degree in every case.

Adolescent↗

PubMed2001

Correction of cleft lip nasal deformity in Orientals using a refined reverse-U incision and V-Y plasty.

A total of 45 patients with cleft lip nasal deformities were operated on between September 1997 and December 1999. We reviewed 35 of them. Out of these, 31 patients had unilateral cleft lip nasal deformities and four patients had bilateral cleft lip nasal deformities. The age range of the patients was from 3 years to 56 years. A reverse-U incision with V-Y plasty was used in 20 patients with mild to moderate unilateral cleft lip nasal deformities. An open rhinoplasty incision combined with the reverse-U incision and V-Y plasty was used in 11 patients with severe unilateral cleft lip nasal deformities. A bilateral reverse-U incision and a trans-columellar incision were used in the four patients with bilateral cleft lip nasal deformities. After advancement of the mucochondrial flap, alar transfixion sutures were used to ensure firm contact between the nasal skin and the redraped reverse-U flap. A composite graft for columellar lengthening was used in six cases of severe unilateral cleft lip nasal deformity and the four cases of bilateral cleft lip nasal deformity. Ancillary procedures included correction of a lateral displacement of the alar base, lip scar revision, a cartilage graft for tip augmentation, iliac bone grafting for correction of hypoplasia of the maxilla or for an alveolar cleft and corrective rhinoplasty. A self-made nasal retainer was applied for 6 months in all patients to maintain the corrected contour of the nostril. The follow-up period ranged from 11 months to 26 months, with an average of 18 months. The final results were evaluated based on the degree of symmetry of the nostrils, the redraping of the alar-columellar web and the exposure of the nostrils. Good results were obtained in 29 patients where alar-columellar web deformities were either absent or minimal and a satisfactory symmetry of the nostrils was achieved. Four patients had fair results and two patients had poor results. In conclusion, we suggest that the reverse-U incision with V-Y plasty is a useful method for achieving symmetry of the nostrils in cleft lip nasal deformities in Orientals. In addition, this technique provides ample advancement and repositioning of the mucochondrial flap and simultaneous correction of the nasal vestibular web.

Adolescent↗

PubMed2001

Blood supply to osteocutaneous free fibula flap and peroneus longus muscle: prospective anatomic study and clinical applications.

From January of 1998 to December of 1999, a total of 24 fibula free flaps in 24 patients were evaluated in a prospective clinical study. Once the perforators were identified, they were dissected toward the parent vessel and labeled according to type. The soleus and flexor hallucis longus muscles of the fibula were dissected, and the proximal part of the pedicle was reached. Subsequently, the configuration of all muscular branches to the peroneus muscle was studied. The types of skin perforators of the peroneal artery were noted as septocutaneous, musculocutaneous, or septomusculocutaneous. A total of 86 perforators were identified in 24 legs. The average number of perforators per leg was 3.58 +/- 0.71. Among them, 22 were musculocutaneous, 31 were septomusculocutaneous, and were 33 septocutaneous. The septocutaneous branches were significantly more distal than the musculocutaneous and septomusculocutaneous perforators. Eight perforators were identified 25 cm distal from the fibular head and six were identified at 15 cm. Five perforators were then identified at each distance of 8, 12, 19, and 22 cm distal from the fibular head. The total number of muscular branches to the peroneus longus was 62, with an average of 2.58 +/- 0.45. Most muscular branches were found between 8 and 16 cm distal to the fibular head. Nine branches were identified at 13 cm distal to the fibular head, eight at 9 cm, and seven at 12 cm. The number of dominant branches with the largest diameter was seven at 13 cm distal from the fibular head, five at 12 cm, five at 16 cm, and two at 11 cm. In summary, when designing an osteocutaneous free fibula flap 10 to 20 cm from the fibular head, it is recommended that a soleus and flexor hallucis longus muscle cuff be included to incorporate these perforators. In contrast, when designing a flap 20 to 30 cm from the fibular head, it is possible to elevate the flap without incorporating the soleus or flexor hallucis muscles.

Blood Vessels↗

PubMed2001

Dynamic control of a continuous-inflow SBR with time-varying influent loading.

The conventional sequential control of Sequencing Batch Reactor (SBR) is designed with fixed time periods for various operation phases. However, both of the flow rates and qualities of influent vary over time, therefore, a big capacity of wastewater equalization unit is required to cope with influent variability. Such an equalization unit increases the total treatment costs of the system, especially in a small-scale wastewater treatment system. Moreover, in using a SBR treating a time-varying influent loading with conventional sequential control, the system performance cannot be optimized. This paper presents the application of on-line ORP and pH monitoring to dynamically control a continuous-inflow SBR with time-varying loading of influent flow rates and water qualities. Experiential results show that the dynamic controlled SBR revealed not only achieved better substrate removal efficiencies, but also reduced treatment costs.

Bioreactors↗

PubMed2001

The feasible sequential control strategy of treating high strength organic nitrogen wastewater with sequencing batch biofilm reactor.

The bio-kinetics and feasible sequential control strategy of treating high strength organic carbon and nitrogen wastewater were investigated by conducting the ABS manufacturing wastewater in a series of Sequencing Batch Biofilm Reactors (SBBRs). The on-line ORP, pH, and DO monitoring parameters were applied to identify the feature-points when ammonification, nitrification, and denitrification ends. The carbonaceous matter removal kinetics in the anaerobic and aerobic reaction stages can be expressed by the Michaelis-Menten equation. High efficiency of organic carbon removal and organic nitrogen ammonification in the anaerobic stage can eliminate the substrate competition and activation inhibition to nitrifying organisms in the following aerobic stage. In the sequencing nitrogen removal processes, the producing time and system ORP values of these feature-points have good function relationships with the influent COD loading rates of SBBR, which can be integrated into a set-point (set-time and set-ORP) sequential control strategy of nitrogen removal. The automatic control operation results revealed ORP was one of the major control parameters of the sequencing nitrogen removal process in SBBR system and high overall removal efficiency were obtained.

Aerobiosis↗

PubMed2001

Development of a real-time control strategy with artificial neural network for automatic control of a continuous-flow sequencing batch reactor.

The purpose of this study is to develop a reliable and effective real-time control strategy by integrating artificial neural network (ANN) process models to perform automatic operation of a dynamic continuous-flow SBR system. The ANN process models, including ORP/pH simulation models and water quality ([NH4(+)-N] and [NOx(-)-N]) prediction models, can assist in real-time searching the ORP and pH control points and evaluating the operation performances of aerobic nitrification and anoxic denitrification operation phases. Since the major biological nitrogen removal mechanisms were controlled at nitrification (NH4(+)-N-->NO2(-)-N) and denitritification (NO2(-)-N-->N2) stages, as well as the phosphorus uptake and release could be completely controlled during aerobic and anoxic operation phases, the system operation performances under this ANN real-time control system revealed that both the aeration time and overall hydraulic retention time could be shortened to about 1.9-2.5 and 4.8-6.2 hrs/cycle respectively. The removal efficiencies of COD, ammonia nitrogen, total nitrogen, and phosphate were 98%, 98%, 97%, and 84% respectively, which were more effective and efficient than under conventional fixed-time control approach.

Ammonia↗

PubMed2000

Second toe to index finger transfer.

Between April 1994 and May 1998, 15 amputated index fingers were treated based on three classifications: group 1 consisted of patients with index finger defects immediately proximal to, yet including, the distal interphalangeal joint, group 2 were those patients with defects from the proximal part of the distal interphalangeal joint to the distal part of the proximal interphalangeal joint and group 3 comprised patients with more proximal defects than group 2. With a total of six men and nine women, seven cases were included in group 1, five in group 2 and three in group 3. For the patients in groups 1 and 2, only a partial length of the second toe was transferred to the index finger, whereas in group 3 the total length of the toe needed to be transferred. The results can be summarised as follows:1. The two-point discrimination of the reconstructed index tip was 2.2 mm for group 1, 2 mm for group 2 and 2.3 mm for group 3.2. In group 1, the average range of motion in the transferred toe was 43.8>> in the distal interphalangeal joint. In groups 2 and 3, the average range of motion in the transferred toe was 30>> and 30.7>> in the distal interphalangeal joint, and 50>> and 39.3>> in the proximal interphalangeal joint, respectively.3. When compared with the contralateral index finger, the pinching power was measured at 83% in group 1, 70% in group 2 and 60% in group 3.4. Excellent results were obtained in group 1, good results in group 2 and fair results in group 3. Accordingly, the more proximal the defect in the index finger, the less satisfactory the result obtained.

Adult↗

PubMed2000

Replantation of avulsed scalps and secondary aesthetic correction.

Five patients with avulsed scalps were treated with replantation between 1992 and 1998. All patients were women age 20 to 36 years. The percentage of the avulsed scalp ranged from 50% to 100% of the whole scalp. The vessels chosen for anastomosis were the superficial temporal artery, occipital artery, and superficial temporal vein. A vein graft harvested from the cephalic vein of the forearm was performed on the venous and arterial sides in 1 patient. Two patients experienced complete survival of the replanted scalp. Three patients showed 40%, 50%, and 80% survival areas, with the remaining defects resurfaced as split-thickness skin grafts. Six months later, the scar areas in the last 3 patients were reconstructed with an expansion of the normal or replanted scalp. The follow-up period ranged from 1 to 7 years. In 4 patients a partial return of sensation in the replanted scalp and motor function of the frontalis muscle were observed. All patients were satisfied with the aesthetic results of their surgery.

Adult↗

PubMed2000

Formation of philtral column using vertical interdigitation of orbicularis oris muscle flaps in secondary cleft lip.

The philtrum in the lip has an important aesthetic significance and is a mark of individual distinction. For patients who have undergone cleft lip surgery, the construction of the philtrum is crucial for restoring a normal appearance to the upper lip. A total of 13 patients with unilateral cleft lip nose deformities were treated for the creation of a philtral column between January of 1998 and February of 1999. Eight of the patients were male and five were female with an age range of 10 to 40 years old. The scar on the philtral column is excised and a full-thickness incision is made down to the orbicularis oris muscle and mucosa. The medial and lateral muscle flaps are then exposed and split into two leaves. The two leaves of each muscle flap are sutured together to create a vertical interdigitation. Any excess skin is not excised but rather closed with 7-0 nylon. The follow-up period ranged from 6 to 15 months, with an average of 10 months. Ten of 13 patients were satisfied with their good surgical results. Two had fair results. One patient experienced a widening of the scar and no improvement in the philtral column. A possible cause for this lack of improvement was a partial disruption of the interdigitated muscle flaps due to the early active movement of the muscle before wound healing. In conclusion, the advantages of this procedure include the creation of an anatomically natural philtrum through preserving the continuity and function of the muscle, sufficient augmentation of the philtral column by the vertical interdigitation of the muscle, relief of skin tension, and no donor-site morbidity.

Adolescent↗

PubMed1999

Mrvi1, a common MRV integration site in BXH2 myeloid leukemias, encodes a protein with homology to a lymphoid-restricted membrane protein Jaw1.

Ecotropic MuLVs induce myeloid leukemia in BXH2 mice by insertional mutagenesis of cellular proto-oncogenes or tumor suppressor genes. Disease genes can thus be identified by viral tagging as common sites of viral integration in BXH2 leukemias. Previous studies showed that a frequent common integration site in BXH2 leukemias is the Nf1 tumor suppressor gene. Unexpectedly, about half of the viral integrations at Nf1 represented a previously undiscovered defective nonecotropic virus, termed MRV. Because other common integration sites in BXH2 leukemias encoding proto-oncogenes contain ecotropic rather than MRV viruses, it has been speculated that MRV viruses may selectively target tumor suppressor genes. To determine if this were the case, 21 MRV-positive BXH2 leukemias were screened for new MRV common integration sites. One new site, Mrvi1 was identified that was disrupted by MRV in two of the leukemias. Ecotropic virus did not disrupt Mrvi1 in 205 ecotropic virus-positive leukemias, suggesting that Mrvi1 is specifically targeted by MRV. Mrvi1 encodes a novel protein with homology to Jaw1, a lymphoid restricted type II membrane protein that localizes to the endoplasmic reticulum. MRV integration occurs at the 5' end of the gene between two differentially used promoters. Within hematopoietic cells, Mrvi1 expression is restricted to megakaryocytes and some myeloid leukemias. Like Jaw1, which is down-regulated during lymphoid differentiation, Mrv1 is downregulated during monocytic differentiation of BXH2 leukemias. Taken together, these data suggest that MRV integration at Mrvi1 induces myeloid leukemia by altering the expression of a gene important for myeloid cell growth and/or differentiation. Experiments are in progress to test whether Mrvi1 is a tumor suppressor gene.

Alternative Splicing↗

PubMed1999

Distraction osteogenesis of free interpositional membranous bone: experimental design.

The purpose of this study is to explore the possibility of bone formation in distraction osteogenesis of the free interpositional membranous bone. Three canine dogs were used as subjects. Two mandibular osteotomies were made in the mandibular body. The oral soft tissue and periosteum of the segment between the two osteotomies were freed from periosteum and the surrounding soft tissue as a free interpositional bone graft 2 cm wide was created. The free interpositional bone was fixed to the proximal mandibular body with a miniplate. The external fixation device was applied to the proximal mandibular body and the distal mandibular body. Mandibular distractions were performed postoperatively at a rate of 1 mm/day for a total of 10-mm distraction for 10 days. The latency period was 1 week in Dog 1, 2 weeks in Dog 2, and 3 weeks in Dog 3. Three dogs were killed 6 weeks after distraction, and interpositional bone specimens were obtained. In Dogs 1 and 2, the free interpositional bone showed severe resorption and had no new bone formation at the distracted area. However, in Dog 3, new bone developed along the distracted gap. Our study demonstrated the possibility of distraction osteogenesis in the free interpositional membranous bone and suggested that free interpositional membranous bone be allowed, under rigid fixation device, to have enough revascularization from surrounding tissue to have osteogenesis for at least 3 weeks or even more.

Animals↗

PubMed1999

Dorsalis pedis tendocutaneous delayed arterialized venous flap in hand reconstruction.

We report two patients whose acute soft-tissue and tendon defects in the hand were treated with a dorsalis pedis tendocutaneous delayed arterialized venous flap between 1994 and 1997. The surviving surface area was 100 percent in both patients. The flap sizes were 10 x 10 cm and 6 x 6 cm. At 2 weeks postoperatively, active flexion and passive extension commenced, and progressive resistance exercises were performed for an additional 5 weeks. Flaps showed a similar color match and skin texture compared with the normal skin of the hand. Advantages of the tendocutaneous delayed arterialized venous flap are that a larger flap can be obtained than when using a pure venous flap or arterialized venous flap; the survival rate of the arterialized venous flap increases, which permits the use of a composite flap; the main artery of the donor site is preserved; thin, nonbulky tissue is used; and elevation is easy, without deep dissection. The disadvantages are the two-stage operation, donor-site scarring, and weak extension of the toes.

Adrenergic alpha-Antagonists↗

PubMed1999

The development of target-eye-view maps for selection of coplanar or noncoplanar beams in conformal radiotherapy treatment planning.

Three-dimensional conformal radiotherapy allows the use of tightly conformed, multiple coplanar or noncoplanar beams. However, visualizing the spatial relationships between the target volume and adjacent critical structures is not always obvious or intuitive. Tools such as beam's eye view (BEV) have aided in this process and been very useful. In this study, a target-eye-view (TEV) map is developed as a functional extension of BEVs. The TEV map for a critical structure is created by checking the BEVs for all gantries and table rotations. For each possible BEV, the amount of overlap between the planning target volume (PTV) and the organ at risk (OAR) is determined. This information is presented in a Mercator spherical map, where the color tone indicates the amount of overlap between the PTV and the OAR. A composite TEV map is then created by summing the TEV grading scores for all OARs. The composite map shows beam orientations with the most overlap being light and the least overlap being dark, thus simplifying the selection of appropriate beam angles. The accuracy of the TEV maps has been confirmed separately with corresponding BEVs generated by a three-dimensional treatment planning system.

Algorithms↗

PubMed1998

Pharyngoesophageal reconstruction with a tubed free radial forearm flap.

Various attempts at reconstruction of pharyngoesophageal defects after ablative surgery have been made to restore the function of the pharyngoesophagus. A tubed free radial forearm flap was used to reconstruct the pharyngoesophagus in 23 patients after resection of neoplasms from May 1989 to October 1995. Nineteen were males and four were females, the average patient age was 62.2 years. The follow-up ranged from 10 to 64 months (mean: 18 months). Oral intake within 3 weeks was possible in 18 patients (78 percent) The immediate postoperative complications were hematoma (n = 1), bleeding (n = 2), infection (n = 3), fistula (n = 4), and venous thrombosis (n = 1). A late complication was stricture of the lower anastomosing site (n = 3). The tubed free radial forearm flap has advantages over free jejunal transfer, including the larger caliber of the vascular pedicle, longer possible ischemic time, no laparotomy with less morbidity of the donor site, and better toleration of radiotherapy. Troublesome disadvantages include stricture and fistula formation at the suture sites. The authors modified the conventional free radial forearm flap to reduce complications. A small monitoring flap supplied by the septocutaneous branch of the radial artery was elevated to check the survival of the flap. During tubing, the vertical suture line was overlapped with a deepithelialized skin flap, and double layer sutures were done to prevent fistula. Two small triangular flaps were designed and inserted at the distal anastomotic site to prevent circular contracture. The outer-layer sutures were anchored to the surrounding rigid structure to withstand shrinkage and circular contraction. With this modification, the incidence of stricture and fistula formation was reduced to 13.0 percent and 17.4 percent, respectively, and these complications could be treated conservatively.

Aged↗

PubMed1998

Severe blepharoptosis: correction by orbicularis oculi muscle and orbital septum resection and advancement.

Using a concept based on cadaveric dissections that the orbital septum could suspend the tarsal plate statically and that the shortened orbicularis oculi muscle would then transmit the frontalis muscle action more effectively, the orbicularis oculi muscle and the orbital septum were advanced to the tarsal plate as a single flap for the correction of blepharoptosis with poor or absent levator function. The redundant portion of the distal flap was resected. From March 1991 to December 1994, 17 patients (24 eyelids) underwent surgery for blepharoptosis with this procedure. Eleven patients were male, and 7 patients had bilateral blepharoptosis. All patients had less than 3 mm of levator function. Patient follow-up ranged from 17 to 52 months, with an average of 35 months. The postoperative result was arbitrarily defined as good when the amount of ptosis was less than 2 mm, fair when the amount of ptosis was 2 to 3 mm, and poor when the amount of ptosis was more than 3 mm. Twelve patients (71%) had good results and 2 patients had fair results. The remaining 3 patients (18%) showed poor results, and reoperation was done with good results in 1 patient and fair results in the other 2 patients. This procedure has several remarkable merits. It is a simple technique with good operative exposure through a single incision at the upper tarsal margin, and it preserves the function of both the frontalis and orbicularis oculi muscles. The main drawback was mild drooping of the upper eyelid for a period of time, so some overcorrection was necessary.

Adolescent↗

PubMed1998

Use of the free innervated dorsalis pedis tendocutaneous flap in composite hand reconstruction.

We used the free dorsalis pedis flap including the extensor digitorum longus or the extensor hallucis brevis, and/or the superficial peroneal nerve to reconstruct composite loss of skin and tendons on the dorsum of the hand. Between February 1992 and February 1996 we treated 7 patients with composite tissue loss on the dorsal hand caused by trauma or burn. Six men and 1 woman had an average age of 26 years (range, 19-42 years). Flap size ranged from 3 x 4 cm to 9.5 x 9 cm. The follow-up period ranged from 10 to 44 months. At 1 week postoperatively, active flexion and passive extension commenced, and progressive resistance exercises were performed for an additional 5 weeks. Two-point discrimination of the transferred flaps averaged 25 mm. Recovery rates for range of motion of the metacarpophalangeal joints in the operated fingers ranged from 83% to 99% (average, 91.4%). All transferred flaps showed similar color match and skin texture compared with the normal skin of the hand. The advantages of this procedure are mass action reconstruction with multiple tendons, provision of similar skin texture, sensory reinnervation, one-stage operation, faster healing with less adhesion formation, and early mobilization. The disadvantages are donor site scarring and weak extension of the toe.

Adult↗

PubMed1998

Treatment of osteonecrosis of the femoral head with free vascularized fibular transfer.

Thirty-one free vascularized fibular bone grafts were performed for treatment of osteonecrosis of the femoral head in 26 patients. Twenty-four men and 2 women ranged in age from 16 to 48 years (mean, 32 years). Twenty-one patients had unilateral disease. Five patients had bilateral disease and underwent staged bilateral free vascularized fibular grafts 3 months apart. Associated etiological factors included alcohol (9 patients), steroid use (7 patients), and trauma (1 patient). The condition was considered idiopathic in the remaining 9 patients. Radiological staging by Ficat included stage I in 1 hip, stage II in 15 hips, stage III in 14 hips, and stage IV in 1 hip. A skin island flap was used for monitoring purposes to check the patency of blood flow to the grafted fibula. One flap failed by venous occlusion and was left as a nonvascularized bone graft. Thirty hips were followed. Pain was relieved in 28 hips (93.3%) and aggravated in 2 hips (6.7%). On radiographic evaluation, 26 hips (86.7%) demonstrated excellent preservation of the femoral head contour. Progressive collapse of the femoral head (>1-2 mm) occurred in two hips, with 1-mm depression in one hip with stage III disease and 2-mm collapse in one hip with stage IV disease. Follow-up ranged from 12 to 40 months (mean, 21 months). In conclusion, even in this relatively short follow-up period, the free vascularized fibular bone graft is an excellent treatment modality for preserving the femoral head and relieving symptoms in patients with osteonecrosis of the femoral head.

Adolescent↗