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P Lobenhoffer

Publications and source records attributed to P Lobenhoffer.

At least 19 recordsLinked to original sources
PubMed1999

[Knee dislocation. Long-term results after operative treatment].

INTRODUCTION: Traumatic dislocation is the most severe ligamentous injury of the knee. The indications for operative and conservative treatment are still controversial. METHODS AND RESULTS: From 1974 to 1994, 38 patients with documented knee dislocation were treated operatively in our department. Thirty-four of these patients were followed up for 3-16 years (mean: 8.6 years). In 29 cases of the follow-up group, reconstruction of both cruciate ligaments was performed. In the remaining cases the cruciate ligaments were left alone. At the time of follow-up, 90 % of the patients showed good knee stability, but 90 % had lack of motion as well. Post-traumatic osteoarthritis was mostly mild to moderate. Thirty-five percent of the patients achieved excellent to good results in the Lysholm Score. CONCLUSIONS: Positive prognostic factors were an age less than 40 years at the time of the accident, a low-energy trauma, e. g., a sports-related injury, early reconstruction of both cruciate ligaments, and initial postoperative functional treatment.

Adolescent↗
PubMed1999

[Chronic instability after posterior cruciate ligament injury. Tactics, techniques, and results].

This article reviews the surgical treatment of chronic posterior knee instability. The treatment rationale includes exact definition of the instability pattern ("envelope-of-motion" of the tibia) by clinical examination, arthrometry and stress radiography. Exact evaluation of the osseous anatomy is mandatory to identify an eventual varus morphotype. This osseous variant in combination with posterior/posterolateral instability should be treated by an osteotomy in every case. The technique of additive osteotomy to correct varus and increase the sagittal tilt of the proximal tibia is described. Ligament reconstruction in chronic posterior knee instability must address the posterior cruciate ligament and the lateral/posterolateral structures in many cases. Patellar tendon grafts, quadriceps tendon grafts or hamstrings can be used for posterior cruciate ligament replacement. Arthroscopic or mini-open techniques may be used for graft placement, direct posterior fixation of the graft via a posterior incision is an option for patellar tendon grafts. Bousquet's biceps plasty or Clancy's biceps tenodesis may be used for posterolateral stabilization; a biceps tendon strip can also be used for lateral collateral ligament reconstruction. Results of surgery are still moderate. In the author's series of chronic posterior/posterolateral instability, 26 cases were treated with posterior cruciate ligament reconstruction and biceps tenodesis. Follow-up at 18 months demonstrated increased stability (mean residual posterior drawer 8 mm at 70 degrees and 20 lb force) and improved knee function (33 % IKDC B, 67 % IKDC C). Presently, surgical treatment of chronic posterior knee instability should be restricted to centers devoted to this problem.

Arthroscopes↗
PubMed1999

Medium-term results of the operative treatment of recurrent patellar dislocation by Insall proximal realignment.

Between 1984 and 1991, 36 patients with the diagnosis of recurrent patellar dislocation were treated operatively using the proximal realignment procedure. Thirty patients were available for follow-up. The average follow-up period was 6.3 years (range 2-9.6 years). The average age at injury was 21.3 years with a predominance of female patients. At follow-up all knees were physically examined. The results were evaluated using the score of Larsen and Lauridsen as well as the Tegner score and subjective assessment. Radiographs from 19 patients (63%) were available for review. At follow-up one patient suffered from a recurrence of patellar dislocation. All patients had stable knee joints and a full range of motion. There was no statistically significant difference between pre- and postoperative sports activity level. Seven patients (23.3%) had excellent results, 12 patients (39.9%) good results and 1 a poor result using the Larsen and Lauridsen score. Subjective assessment revealed the operative result as very good, good or satisfactory in 90%. Patellofemoral osteoarthritis was seen in 7 of 19 patients (36.8%). With a proximal realignment procedure good clinical results can be achieved for recurrent patellar dislocation. Subjective satisfaction with this procedure is rated as good. It is successful in preventing redislocation.

Adolescent↗
PubMed1999

Immunohistochemical localization of collagen VI in arthrofibrosis.

Arthrofibrosis is a disabling complication after knee trauma and surgery. Clinically, it is characterized by pain and joint stiffness due to massive connective tissue proliferation. In similar pathological conditions with fibrotic transformation such as lung fibrosis or superficial fibromatoses, an increased expression of collagen type VI has been reported. Collagen VI, which forms a filamentous network, is thought to serve as an anchoring element between collagen I/III fibrils and basement membranes and as a cell binding structure. Collagen VI may also play a contributing role in the pathogenesis of arthrofibrosis. The aim of the present study was therefore to demonstrate the localization and distribution of type VI collagen in arthrofibrotic tissue. Tissue samples from the infrapatellar fat pad and intercondylar synovia of 13 patients suffering from arthrofibrosis were taken at surgery. The expression of type VI collagen was studied immunohistochemically using an immunoperoxidase method for light microscopic visualization. Histologic analysis showed a synovial hyperplasia with inflammatory cell infiltration and vascular proliferation. Compared with normal synovial tissue, type VI collagen was widely distributed as a network subsynovially and around the capillary walls. The results of the present study suggest that dysregulation of collagen VI synthesis could be an important contributing factor in the complex mechanisms of disordered matrix protein deposition leading to arthrofibrosis.

Adolescent↗
PubMed1999

Closed reduction/percutaneous fixation of tibial plateau fractures: arthroscopic versus fluoroscopic control of reduction.

OBJECTIVE: To evaluate arthroscopic versus fluoroscopic reduction and percutaneous fixation of lateral tibial plateau fractures of AO/OTA Types 41.B1 to 41.B3. DESIGN: Prospective study. SETTING: University hospital. PATIENTS AND INTERVENTION: One hundred sixty-eight patients underwent operative treatment for a tibial plateau fracture from 1988 to 1995. Thirty-three of these patients had monocondylar fractures of the lateral plateau that were treated by percutaneous reduction and fixation techniques. In the first ten cases, arthroscopic control of reduction was used. The following twenty-three consecutive cases were treated by reduction and fixation solely under fluoroscopic control. The arthroscopy group was followed for a mean of fifty-two months and the fluoroscopy group for thirty-eight months. RESULTS: Nine of ten cases of the arthroscopy group had an excellent or good result in Rasmussen's knee score at follow-up. One patient with an unreduced anterolateral depression zone despite arthroscopic surgery required a total knee prosthesis after eighteen months. Sixteen cases in the fluoroscopy group met the follow-up criteria. Fifteen were graded good or excellent in Rasmussen's clinical score; sixteen were excellent or good in the radiological score. One patient claimed chronic medial joint line pain after a lateral split fracture and had arthroscopy revealing chondral degeneration on the medial side but had no pathological findings in the lateral compartment. No secondary meniscus or ligament surgery was performed in the follow-up period. CONCLUSIONS: Percutaneous treatment of fractures of the tibial plateau can be performed using arthroscopy as well as image intensification to control reduction of the joint surface. We were not able to demonstrate any significant benefit from arthroscopy compared with fluoroscopic reduction. Reduction under image intensification is technically easier in our practice, especially in serial fractures and multiply injured patients. We reserve arthroscopy for cases with significant ligament injuries and for children with fractures of the median eminence.

Adolescent↗
PubMed1998

[Interim results of surgical therapy of patellar dislocation by Insall proximal reconstruction].

Between 1984 and 1991, 57 patients with diagnosis of an acute or recurrent patellar dislocation were treated operatively using proximal realignment with vastus medialis transfer and lateral release (Insall operation). A total of 45 patients (15 with acute and 30 with recurrent patellar dislocation) were reviewed at an average follow-up of 6.5 years (2-9.6 years). The average age at injury was 21.5 years, with a predominance of female patients. Follow-up examination included routine knee examination, clinical review using the modified knee scoring scale of Larsen and Lauridsen, sports activity level and subjective satisfaction. Radiographics from 27 patients (60%) were evaluated. One patient from each group suffered recurrence of patellar dislocation. All patients had stable knee joints and a full range of motion. There was no statistical difference in the pre- and postoperative sports activity level in both groups. Three patients (19.9%) with acute patellar dislocation and seven patients (23.3%) with recurrent patella dislocation had excellent results using the Larsen and Lauridsen score scale. Ten patients (66.6%) with acute and 12 (39.9%) with recurrent dislocation had good results. One patient with recurrent patellar dislocation had a fair result. Subjective evaluation revealed the operative result in 93% of cases as very good, good or satisfactory. Patellofemoral osteoarthritis was seen in 11 (40.7%) of 27 patients. Our results show good clinical results for the treatment of acute patellar dislocation in young, active patients with the proximal realignment procedure. The recurrence rate of patellar dislocation can be reduced for acute and recurrent patellar dislocation. Subjective satisfaction with this procedure is rated very good.

Acute Disease↗
PubMed1998

[Internal osteosynthesis after unstable pelvic ring fracture in a 3-year-old child].

A 3-year-old child was trapped under the heavy load of a forklift truck and sustained an unstable pelvic ring fracture (Tile type C) with complete SI disruption, disruption of the public symphysis and external rotation injury of the contralateral SI joint. An immediate internal fixation was performed, exposing the SI joint and the public symphysis simultaneously. For stabilization an H-plate was used for anterior plate fixation of the SI joint, while the public symphysis was stabilized by screws and cerclage wires. After one revision of the symphysis the clinical course was uneventful with anatomical healing of the pelvic ring. The implants were removed after 4 months. Clinical and radiological follow-up after 12 months showed no signs of maldevelopment of the pelvic ring.

Bone Plates↗
PubMed1998

[Can knee joint proprioception by reconstruction of the anterior cruciate ligament be restored? A prospective longitudinal study].

Knee proprioception was assessed in 20 healthy volunteers, 10 patients with acute anterior instability and in 20 patients with chronic anterior instability preoperatively as well as after 3 and 6 months postoperatively. To determine proprioception, an angle reproduction test was performed. There were no differences between the right and the left knee joint or between men and women. Best proprioception was measured near full extension. The acute trauma causes massive damage of the proprioception, which could be improved significantly by rehabilitation. However, rehabilitation could not restore proprioception. 3 months postoperatively, there was a slight decrease of proprioception as compared to the preoperative values, but 6 months after reconstruction, restoration of proprioception was documented near full extension and full flexion. In the mid range position, the proprioception could not be restored. There was no difference between open and arthroscopic techniques. The highest correlation was found between proprioception and patient's satisfaction.

Adult↗
PubMed1998

[Golden standard: patellar tendon-plasty--technique and management of postoperative complications].

ACL reconstruction with a patellar tendon autograft has reached a high grade of perfection. Surgery can be performed mini-open or arthroscopically, both techniques are presently equal in morbidity and results. The optimal insertion areas for the graft have been defined and can be controlled intra- and postoperatively by radiographs. The bone blocks of the graft allow for stable fixation and an aggressive functional rehabilitation program stressing active full extension of the joint. Disadvantages are a certain donor site morbidity and a rate of restrictions in range-of-motion. The management of arthrofibrosis should address the pathogenesis. Localized arthrofibrosis is caused by a mechanical conflict in the knee and removal of the mechanical block will usually solve the problem. Generalized arthrofibrosis is a complex process involving the entire joint and resulting in a wide-spread proliferative reaction of the connective tissue. The surgical management must be more complex involving open debridement and capsulotomies.

Anterior Cruciate Ligament↗
PubMed1997

[Definition of complex trauma and general management principles].

Complex joint trauma is a term reserved for specific and severe injuries that include two or more structural elements of the joint. These structural elements are the articulating bones, the major ligaments of the joint, the local soft tissue envelope and the neurovascular structures. Complex joint trauma has a high risk for complications and requires a special treatment algorhythm. A staged surgical protocol with initial soft tissue debridement, closed joint reduction and external fixation of the extremity followed by secondary reconstructive surgery after soft tissue recovery is suggested.

External Fixators↗
PubMed1997

[The potentials of minimally invasive surgical measures in the knee joint].

The treatment of knee joint injuries has seen marked development in the last few years. The surgical trauma of intra-articular fracture reconstruction has been reduced significantly. Retrograde nailing, percutaneous plating and specific exposures to distal femur and proximal tibia fractures have been established. Percutaneous osteosynthesis controlled by arthroscopy or fluoroscopy is widely used for B-fractures of the tibial plateau. Injectable bone mineral cement adds to reduced trauma of surgical treatment of these fractures. In all knee ligament procedures, arthroscopy is obligatory for diagnosing and conducting meniscus surgery. Ligament reconstruction should be performed either arthroscopically or by a limited arthrotomy, the results being comparable at present.

Femoral Fractures↗
PubMed1997

[Particular posteromedial and posterolateral approaches for the treatment of tibial head fractures].

Tibial plateau fractures with depression of posterior aspects of the proximal tibia cause significant therapeutic problems. Posterior fractures on the medial side are mainly highly instable fracture-dislocations (Moore type I). Posterolateral fractures usually cause massive depression and destruction of the chondral surface. Surgical exposure of these fractures from anterior requires major soft tissue dissection and has a significant complication rate. However, incomplete restoration of the joint surface results in chronic postero-inferior joint subluxation, osteoarthritis and pain. We present new specific approaches for posterior fracture types avoiding large skin incisions, but allowing for atraumatic exposure, reduction and fixation. Posteromedial fracture-dislocations are exposed by a direct posteromedial skin incision and a deep incision between medial collateral ligament and posterior oblique ligament. The posteromedial pillar and the posterior flare of the proximal tibia are visualized. The inferior extent of the joint fragment can be reduced by indirect techniques or direct manipulation of the fragment. Fixation is achieved with subchondral lag screws and an anti-glide plate at the tip of the fragment. Posterolateral fractures are exposed by a transfibular approach: the skin is incised laterally, the peroneal nerve is dissected free. The fibula neck is osteotomized, the tibiofibular syndesmosis is divided and the fibula neck is reflected upwards in one layer with the meniscotibial ligament and the iliotibial tract attachment. Reflexion of the fibula head relaxes the lateral collateral ligament, allows for lateral joint opening and internal rotation of the tibia and thus exposes the posterolateral and posterior aspect of the tibial plateau. Fixation and buttressing on the posterolateral side can be achieved easily with this approach. In closure, the fibula head is fixed back with a lag screw or a tension-band system. These two exposures can be combined in bicondylar posterior fracture situations. 168 cases with tibial plateau fractures had ORIF in the authors' institution from 1988 to 1994. 26 of these patients had a total of 29 posterior exposures to treat their fractures (9 posteromedial, 12 posterolateral, 3 combined posteromedial/posterolateral and 2 posterior/anterior exposures). No specific complications occurred related to these exposures, i.e. no skin slough, no infection, no nerve palsy. The mean duration of follow-up was 4 years. Twenty-one cases healed uneventfully: 12 were excellent in Rasmussen's clinical score, 8 were good and 1 was fair. Seven patients were excellent in the radiological score, 13 good and 1 fair. Five of the 26 cases had revision surgery: 3 patients developed valgus or retrocurvatum deformity and were successfully treated by an osteotomy. They obtained a good result at follow-up. Two fractures in elderly patients were revised to an endoprosthesis.

Bone Nails↗
PubMed1997

[New developments in joint surgery].

The treatment of joint injuries has seen a marked development in the last years. The surgical trauma of articular reconstruction was reduced and our deeper understanding of the mechanism of connective tissue healing influenced the rehabilitation program after joint injuries significantly. Indirect soft-tissue sparing reduction techniques can be applied to most joint fractures and improved fixation techniques using intraoperative fluoroscopy or arthroscopy allow to avoid vast exposures of the joint. The process of ligament healing requires joint movement and a certain stress to the healing tissue in order to achieve optimum scar strength, stiffness and remodeling. Immobilisation thus should be avoided completely after ligament injuries and certain lesions can be treated non-operatively with a high success rate (MCL rupture, ankle sprain, elbow dislocation). In other injuries, surgery should stabilize the joint thus allowing functional rehabilitation (cruciate ligament tears, shoulder dislocation).

External Fixators↗