Biomedical subjects

Matthew J Matava

Publications and source records attributed to Matthew J Matava.

13 recordsLinked to original sources

PubMed2006

The effect of gamma irradiation on anterior cruciate ligament allograft biomechanical and biochemical properties in the caprine model at time zero and at 6 months after surgery.

BACKGROUND: High levels of gamma irradiation are required to eliminate the risk of bacterial and viral transmission during implantation of musculoskeletal allografts. The effects of high levels of gamma irradiation on anterior cruciate ligament allograft biomechanics are still not known. HYPOTHESIS: High-dose gamma irradiation (4 Mrad) adversely affects anterior cruciate ligament allograft biomechanics at surgery and at 6 months after surgery and affects biochemistry at 6 months. STUDY DESIGN: Controlled laboratory study. METHODS: Bilateral anterior cruciate ligament reconstructions were performed in 18 adult goats, with one knee receiving an irradiated patellar tendon allograft (4 Mrad) and the other receiving a frozen control allograft (0 Mrad). In 6 recipients (time zero group), graft pairs were tested immediately after sacrifice, and load relaxation of the femur-allograft-tibia preparation was measured during cyclic anterior displacement. Twelve recipients received bilateral anterior cruciate ligament reconstructions, staged 2 months apart, and were sacrificed a mean of 6 months postoperatively. Load relaxation and tensile failure testing were performed, followed by allograft biochemistry assessment. RESULTS: At time zero, irradiated grafts showed less load relaxation than did contralateral controls, but by 6 months, the trend had reversed because of decreases in control graft relaxation, with no changes in irradiated graft relaxation. By 6 months, irradiated grafts showed lower stiffness and maximum force compared to controls but no differences in modulus, maximum stress, or biochemistry. CONCLUSION: High levels of gamma irradiation affect anterior cruciate ligament allograft subfailure viscoelastic and structural properties but not material or biochemical properties over time. CLINICAL RELEVANCE: Although high levels of gamma irradiation may inactivate infectious agents, this treatment is not a feasible clinical option because of altered allograft biomechanics.

Animals↗

PubMed2006

Proximity of the popliteal artery to the PCL during simulated knee arthroscopy: implications for establishing the posterior trans-septal portal.

This study defines the sagittal distance from the posterior cruciate ligament (PCL) to the popliteal artery under simulated arthroscopic conditions. This information is relevant for posterior knee arthroscopy, particularly for the safe establishment of the posterior trans-septal portal. Measurements from the PCL to the popliteal artery were made on sagittal magnetic resonance images obtained in a previous study of 10 fresh-frozen cadaveric knees. The mean sagittal distance from the mid-PCL to the popliteal artery was 29.1 +/- 11 mm (range: 18-55 mm). The mean sagittal distance from the proximal PCL fovea to the popliteal artery was 9.7 +/- 5 mm (range: 3-16 mm). The results of this study provide the arthroscopist working in the posterior compartments of the knee with a more detailed knowledge of the anatomic relationship between the PCL and popliteal artery. This knowledge will help minimize the risk of iatrogenic vascular injury during arthroscopic knee surgery.

Aged↗

PubMed2006

Complications of anterior cruciate ligament reconstruction: graft issues.

Anterior cruciate ligament reconstruction has become one of the most common arthroscopic procedures performed on the knee. Complications from this reconstructive surgery, although uncommon, can be devastating to the overall function of the knee. Several strategies exist to avoid potential complications related specifically to graft harvest and implantation, and to complications related to the bone-patellar tendon-bone and hamstring autografts, and patellar tendon allograft, the most common grafts currently used.

Anterior Cruciate Ligament↗

PubMed2005

Partial-thickness rotator cuff tears.

Partial-thickness tears of the rotator cuff have been diagnosed with increased frequency because of a heightened awareness of the condition by clinicians and improved diagnostic methods. Research into the causes, natural history, and optimal treatment of this condition lags behind that of full-thickness tears. However, despite the limitations in the existing literature, there has emerged a consensus among shoulder experts that partial-thickness rotator cuff tears should be aggressively treated in the active athlete because of the unfavorable natural history of these lesions and success of accepted surgical algorithms. This review will provide an overview of the theories regarding the origins of partial-thickness rotator cuff tears, discuss the relative accuracy of accepted diagnostic techniques, and summarize the indications and methods of operative repair with an emphasis on the results of various treatment approaches.

Age Factors↗

PubMed2004

Ankle syndesmosis sprains in national hockey league players.

BACKGROUND: Although syndesmosis sprains are less common in sports than lateral ankle sprains, they represent a significant source of morbidity. Several studies have described the increased recovery time for these injuries in a variety of sports. No previous study has described this injury in hockey players. HYPOTHESIS: Syndesmosis ankle sprains require a longer recovery time and are less common than lateral ankle sprains in elite hockey players. STUDY DESIGN: Uncontrolled retrospective review. METHODS: The medical records of the St Louis Blues (1994-2001) and Dallas Stars (1991-2001) National Hockey League teams were reviewed by the head athletic trainers. Ankle sprains were identified and divided into 2 groups: syndesmosis and lateral sprains. Player demographics, treatment, and time lost to play were recorded for each injury. RESULTS: Fourteen players were diagnosed with syndesmosis sprains, and 5 players sustained lateral sprains during this time period. Mean time to return to play in games was 45 days (range, 6-137 days) for syndesmosis sprains versus 1.4 days (range, 0-6 days) for lateral sprains. CONCLUSIONS: Syndesmosis sprains represent a significant injury in hockey players with an extended time lost and, unlike in other sports, are a more common injury than lateral ankle sprains.

Ankle Injuries↗

PubMed2004

Osteochondritis dissecans of the knee: long-term results of excision of the fragment.

Optimal treatment of osteochondritis dissecans of the knee has been controversial. Various treatment methods have resulted in good short-term results. Unfortunately, the age range of the patients who typically require treatment of this disorder is young enough that long-term results become critical. We did a retrospective review to evaluate our hypothesis that simple excision of a loose osteochondritis dissecans fragment results in a higher percentage of unacceptable outcomes when compared with treatment methods that preserve the articular cartilage. Between 1982 and 1993, 30 knees in 29 patients had arthroscopic or arthroscopically assisted surgical excision of a symptomatic loose osteochondritis dissecans lesion of the knee. Seventeen patients who had excision were available for followup. There were 12 males and five females. The average age of the patients at the time of surgery was 26 years (range, 12.5-38 years). The average length of followup was 8.9 years (range, 4-15 years). Results were graded using the Hughston rating scale for osteochondritis dissecans. Only six of 17 patients (35%) had a good or excellent result. Eleven of 17 (65%) had a fair or poor result. We think our results at intermediate followup support our hypothesis, and we recommend aggressive attempts to preserve the articular cartilage and avoid excision of the fragments when possible.

Adolescent↗

PubMed2004

Removal of a retained Herbert-Whipple screw with use of the Osteochondral Autograft Transfer System (OATS) core harvester: a case report.

After a revision procedure is performed to address a full-thickness chondral defect of the knee, hardware removal can be challenging. We describe using a core harvester, the Osteochondral Autograft Transfer System (OATS; Arthrex, Naples, Fla), to remove a Herbert-Whipple screw placed earlier in a failed attempt to fix an osteochondritis dissecans lesion on the lateral aspect of the medial femoral condyle. This hardware removal technique can be performed either arthroscopically or in an open fashion and may also be used with other revision procedures (ie, revision anterior cruciate ligament reconstruction) in which an embedded, poorly visualized, or stripped screw must be removed.

Adult↗

PubMed2003

Complications of treatment of acromioclavicular and sternoclavicular joint injuries.

Although common, AC joint injuries and their treatments are not benign. The injury itself and both nonsurgical and surgical treatments may result in complications yielding persistent pain, deformity, or dysfunction. Sternoclavicular joint injuries are far less common and are typically the result of higher energy trauma. As such, the associated complications may be more serious. Familiarity with the potential complications of these injuries can help the treating physician to develop strategies to minimize their incidence and sequelae.

Acromioclavicular Joint↗

PubMed2003

Gender differences in surface rolling and gliding kinematics of the knee.

The purpose of the current study was to determine whether knee surface rolling and gliding kinematics differed between genders during open and closed kinetic chain movement conditions. Eleven unimpaired adults (six men and five women) participated in this study. Sagittal plane path of instant center of rotation measurements were obtained with videographic motion analysis and applied to a mathematical knee model from which joint surface rolling and gliding kinematics were obtained. In addition, normalized electromyographic data were collected from subjects' quadriceps and hamstring muscles. During closed kinetic chain knee extension, as the knee approached terminal extension, female participants showed significantly greater relative joint surface gliding than male participants. Female participants also extended the knee in the closed kinetic chain with less relative hamstring activity than males. The relationship between joint surface gliding and relative hamstring activity in females during closed kinetic chain knee extension may explain, in part, the greater incidence of noncontact anterior cruciate ligament injury that occurs in females.

Adult↗

PubMed2002

Limb dominance as a potential etiologic factor in noncontact anterior cruciate ligament tears.

A retrospective case series analysis of 80 patients (44 males and 36 females) who presented with acute, unilateral, noncontact anterior cruciate ligament (ACL) tears was performed. The role of limb dominance as a possible etiologic factor in noncontact ACL tears was investigated and the gender-specific relationship was determined. Patients were questioned about the nature of their injury and asked to list their preferred upper and lower extremities for writing, throwing, and kicking-activities previously used to define upper and lower extremity dominance. The relationships between limb dominance, side of injury, and gender were assessed. Mean patient age was 27.8 years. The left knee was involved in 54% of patients and the right knee in 46%. Eighty-nine percent of the study group identified themselves as right-hand dominant for writing, 91% were right-hand dominant for throwing, and 89% were right-leg dominant for kicking. Overall, there was no significant correlation between the side of injury and dominant limb for writing (P=.84), throwing (P=.68), or kicking (P=.99). There also was no significant gender effect on the relationship between limb dominance and side of injury (P=.65). Limited numbers precluded an analysis of specific limb-dominant sports activities as potential risk factors. The results of this pilot study suggest limb dominance is not a significant etiologic factor for noncontact ACL tears.

Adolescent↗

PubMed2002

Knee joint movements in subjects without knee pathology and subjects with injured anterior cruciate ligaments.

BACKGROUND AND PURPOSE: Although weight-bearing (WB) exercise and increased hamstring muscle activity may contribute to knee joint stability in knees with an injured anterior cruciate ligament (ACL), the relationship among ACL integrity, muscle activity, and joint surface motion is not fully understood. The purpose of this study was to investigate whether knee joint rolling and gliding movements and electromyographic (EMG) activity differed between subjects with injured ACLs and subjects without knee pathology. SUBJECTS: Fifteen subjects with injured ACLs (9 men and 6 women; mean age=26 years, SD=7, range=18-36) and 15 age- and sex-matched subjects without knee pathology (9 men and 6 women; mean age=25 years, SD=6, range=18-36) participated in the study. METHODS: Sagittal-plane knee joint rolling and gliding movements and lower-extremity EMG activity were measured during non-weight-bearing (NWB) and WB movements. Mixed-model analyses of variance were conducted to analyze rolling and gliding and EMG data. RESULTS: During NWB knee extension, greater joint surface gliding occurred in knees with injured ACLs at full knee extension. During WB knee extension, greater gliding occurred in knees with injured ACLs throughout the range of motion tested. No differences in EMG activity occurred between groups. DISCUSSION AND CONCLUSION: The results suggest that, in the absence of increased hamstring muscle activity, anterior tibial displacement is not reduced in knees with injured ACLs during WB movement.

Adult↗

PubMed2001

Postarthroscopy surgical site infections: review of the literature.

The use of arthroscopy for both diagnosis and operative intervention has been increasing steadily since its introduction in the 1970s. It is generally associated with fewer complications and shorter times to mobilization than are open procedures. Overall reported rates of complications are low (0.1%-0.6% of procedures). This review focuses on infectious complications of arthroscopy, which are rare (0.01%-0.48% of procedures) but result in significant morbidity for the patient when they occur. The most commonly reported causative organisms are staphylococci. Several outbreaks have been reported related to breaks in infection control or to contaminated instruments. Suggested risk factors include use of intra-articular corticosteroids, prolonged tourniquet time, patient's age >50 years, failure to prepare the surgical site again before conversion to arthrotomy, procedure complexity, and a history of previous procedures. However, most reports use variable and unclear definitions of infection, which makes it difficult to draw firm conclusions.

Arthroscopy↗

PubMedDate not supplied

Mechanical properties of bioabsorbable meniscal arrows as a function of tear location: an ex vivo experimental study.

BACKGROUND: Ex vivo studies have established that arrow fixation of meniscal tears is inferior to vertical sutures and is dependent on arrow length, although the influence of tear location is not known. HYPOTHESIS: Arrow length and tear location influence the mechanical properties of meniscal arrows. STUDY DESIGN: Controlled laboratory study. METHODS: A longitudinal incision was created either 2 mm or 7 mm from the periphery in 70 bovine medial menisci. Each was repaired with a meniscal arrow (10, 13, or 16 mm) or a single vertical suture and subjected to load-to-failure testing and video-graphic analysis. RESULTS: Mode of failure (P <.0001), maximum force (P <.0001), stiffness (P <.01), 2-mm gap force (P <.03), and ultimate gap formation (P <.002) were all directly related to arrow length. Sixteen-mm arrows and suture exhibited similar, superior mechanical properties. Tear location significantly influenced properties of 10-mm and 16-mm but not 13-mm arrows. Ten-millimeter arrows displayed the worst performance. CONCLUSIONS: Mechanical properties of meniscal arrows depend on tear location and arrow length. CLINICAL RELEVANCE: Sixteen-millimeter arrows are a possible alternative to suture for repair of central tears. Thirteen-millimeter arrows may be effective for central and peripheral tears. Ten-millimeter arrows should not be used.

Absorbable Implants↗