Frank H. Bassett

Osseous injury associated with acute tears of the anterior cruciate ligament

Multiplanar spin-echo magnetic resonance imaging was performed on 54 patients with acute complete anterior cruciate ligament tears. Imaging was done within 45 days of index anterior cruciate ligament injury. Spin- echo T1- and T2-weighted images were used to deter mine the lesion morphology and location. Only the T2- weighted sagittal images were used for the incidence assessment; T2-weighted spin-echo imaging reflects free water shifts and best indicates the acute edema and inflammatory changes from injury. Eighty-three percent (45 of 54) of the knees had an osseous contusion directly over the lateral femoral con dyle terminal sulcus. The lesion was highly variable in size and imaging intensity; however, the most intense signal was always contiguous with the subchondral plate. Posterolateral joint injury was seen in 96% (43 of 45) of the knees that had a terminal sulcus osseous lesion determined by magnetic resonance imaging. This posterolateral lesion involves a spectrum of injury, in cluding both soft tissue (popliteus-arcuate capsuloliga mentous complex) and hard tissue (posterolateral tibial plateau) injuries. The consistent location of the osseous and soft tissue injuries underscores a necessary similar mechanism of injury associated with these acute anterior cruciate ligament tears. Based on these characteristic findings, several proposed mechanisms of injury are discussed.

Talar impingement by the anteroinferior tibiofibular ligament. A cause of chronic pain in the ankle after inversion sprain.

Seven patients who had pain in the anterior aspect of the ankle were found to have a thickened distal fascicle of the anteroinferior tibiofibular ligament. Each patient had a history of an inversion sprain of the ankle followed by chronic pain in the anterior aspect of the ankle. The thickened distal fascicle was resected without loss of stability of the ankle. Five patients needed débridement of an area of abraded hyaline cartilage on the anterolateral aspect of the talus. Six patients were followed for a mean of thirty-nine months (range, twenty-four to fifty-nine months). Four of them had no pain in the ankle or limitation in activities, and two reported marked improvement, with only occasional pain in the ankle related to overuse. A separate distal fascicle of the anteroinferior tibiofibular ligament is present in most human ankles and can be a cause of talar impingement, abrasion of the articular cartilage, and pain in the anterior aspect of the ankle. Resection of this ligament usually will alleviate the pain caused by the impingement.

Histochemical correlates of hamstring injuries

This study reports the histochemical fiber type com position of the human hamstring muscles. Muscle spec imens from necropsy specimens were obtained from seven locations in the hamstring, four locations in the quadriceps, and one location in the adductor magnus. The hamstring muscles are shown to have a relatively high proportion of Type II fibers. Type II fibers are more involved with exercise of higher intensity and force production and it is postulated that the hamstrings are capable of high intrinsic force production. The ham strings are two-joint muscles and are, therefore, subject to increased stretch and force production extrinsically by motion at the hip and knee. It is proposed that high levels of tension in the hamstrings produced by intrinsic force production and extrinsic stretch may make them prone to injury in periods of intense muscular activity. This proposal is also relevant to other frequent athletic muscle injuries.

Anterior cruciate ligament allograft transplantation: Long-term function, histology, revascularization, and operative technique

In recent years much effort has been devoted to finding a satisfactory replacement for the injured ACL. None of the reconstruction techniques used in the past can be considered ideal because of their inability to dupli cate the complex geometry, structure, and function of the ligament. Current advances in allograft transplan tation and cryopreservation have led us to design and implement an experimental model for testing the feasi bility of cryopreserved ACL allotransplantation. Groups of dogs were used to evaluate the effect of cryopreservation on ligament strength and to compare the relative performance of both autograft and allograft ACL transplants up to 18 months after implantation. The ligaments were examined mechanically, histologi cally, and microangiographically. The cryopreservation process and duration of stor age had no effect on the biomechanical or structural properties of the ligament. The mechanical integrity of the allografts was similar to that of the autografts, with both achieving nearly 90% of control ligament strength by 36 weeks. Revascularization approached normal by 24 weeks in both autograft and allograft. No evidence of structural degradation or immunological reaction was seen. Based on these results, we believe that a cryopre served ACL allograft can provide the ideal material for ACL reconstruction. We have outlined a surgical tech nique for harvesting and implanting this graft clinically.

Longitudinal rupture of the peroneal tendons

To determine more precisely the injury mechanism of the peroneal tendon longitudinal tear, we studied 15 cadaveric lower extremities. Our study was motivated by our observation from a retrospective study of ath letes treated by one surgeon (FHB) over a 17-year period. Eight patients who sustained lateral ankle sprains by plantar flexion and inversion of the foot on the leg also had longitudinal tears (1 to 3 cm) of the peroneal tendon—five in the peroneus longus and three in the peroneus brevis. All of the lateral ankle sprains were successfully managed nonoperatively. However, even after a period of rehabilitation, when their ankles should have been asymptomatic, the patients continued to complain of persistent lateral ankle swelling, popping, and retrofibular pain. On physical examination, all ankles were clinically stable. Palpable retrofibular pop ping occurred with active foot rotation. There was no evidence of peroneal tendon instability. Radiographs were normal and tenograms were suggestive of pero neal tendon injury but did not have the specificity to reveal the rupture. Primary suture repair of this peroneal tendon split was performed and gave excellent long- term results. The cadaveric studies revealed that the tear of the tendon could occur in the 25° to 15° range of plantar flexion as the peroneus longus impinged against the tip of the fibula and as the peroneus brevis impinged against the lateral wall of the peroneal groove or against the longus tendon.

Cryotherapy-induced nerve injury

Cryotherapy is a frequently used therapeutic modality in the treatment of athletic injuries. Peripheral nerve injury can result from the use of cryotherapy and cause temporary disability for the athlete. Six cases of periph eral nerve injury are reviewed. All cases resolved spon taneously. To avoid this complication, one should con sider the location of major peripheral nerves, the thick ness of the overlying subcutaneous fat, and the duration of tissue cooling.

The prolonged burner syndrome

Over the course of a single football season, six players evaluated by the medical staff had burners that dis played a prolonged neurologic recovery. These players were examined and subsequently evaluated with iso kinetic testing and electrodiagnostic studies to eluci date better the short-term natural history of the pro longed burner syndrome. Evidence of muscular weak ness at 72 hours postinjury best correlated with positive electrodiagnostic findings. No correlation was found between the initial physical examination findings and the results of electrodiagnostic testing. Isokinetic strength evaluation demonstrated many relative strength differences that were difficult to discern with manual muscle testing. The return of a player to athletic competition following this injury should largely be based on the clinical examination.

Pathological Changes in the Hip in Cerebral Palsy: Incidence, Pathogenesis, and Treatment

The purposes of t.his paper are to emphasize the frequmemicy of coxa valga amid acetabular changes in the pat ient uiith cerebral palsy, to (‘all attentholmi t (I the forces that may cause such defonmuities, and to) stress the imuportance (If early (‘olrre(’tiomm of these forces iii t.hie prevention of deformities. The indications aum(l advantages of distal teliotolniy of the gnacilis amid medial hiamst nimig teiidomis in the corre(’t i(IIi of (Ifl (If the mnamiy def(Inmiiiuig forces on the hip in cerebral palsy will also 1)e discussed. Numnerous theories have beemt proposed as to the factolns that may o’ause pat hololgical changes in the hip in the patient uiith cerebral palsy. One theory (‘(1mmeerns the role that tractiomi l.y the hip abductors plays imi stimiiulating epiphyseal grouvth (If the greater t..rochantem’ amid shaping the coiitoumn of the neo’k of the femur.

False Aneurysm of the Profunda Femoris Artery After Subtrochanteric Osteotomy and Nail-plate Fixation

1. A case of false aneurysm of the profunda femoris artery caused by an excessively long screw used to fix a Jewett nail-plate to the upper part of the femoral shaft is presented. The aneurysm did not become symptomatic until ten years after insertion of the screw. 2. If a painful pulsating mass appears in the thigh after an operation about the hip in which drills and screws were used, one should suspect a false aneurysm.

An algorithm for arthroscopy in the over-50 age group:

We conducted a retrospective study to identify the preoperative variables that correlated with a successful outcome for knee arthroscopy in patients over the age of 50. We mailed questionnaires to 94 patients (57 responded) and reviewed their medical records and radiographs. A modified Hospital for Special Surgery knee rating system was devised. The average followup was 33 months. The percentage of those who felt they had successful results decreased with time: 82.8% felt their knees had improved immediately after postoper ative rehabilitation; this decreased to 78.1% at 6 months, 73.5% at 1 year, 65.5% at 2 years, and 50.0% at 3 years. Therefore, the subjective success rate was 67%. We performed statistical analysis of all variables to determine which had a beneficial or detrimental effect on outcome. In addition, we devised an equation to allow postoperative prediction of score. We found that age was not a factor and that radiographic findings had the greatest impact on postoperative results.