Arthroscopic subacromial decompression.

In this study, we analyzed the results of two series of patients treated for impingement syndrome by undergoing arthroscopic subacromial decompression (ASD). Patients had not responded to nonoperative treatment. Group 1 included 112 consecutive patients (average age, 41 years) with 96 (77%) patients available for 2-year follow-up. Group 2 (28 patients, 29 shoulders; average age, 43 years; range, 22 to 72) had ASD and the subacromial space digitally palpated to determine if adequate decompression was performed. Twenty-two (85%) of 26 shoulders were available for follow-up. At follow-up, pain, function, range of motion, strength, impingement signs, and patient satisfaction were assessed. In group 1, according to the Neer criteria, 48% of the patients were graded as satisfactory and 52% unsatisfactory. Workers' Compensation patients had a satisfactory rate of 32%, whereas non-Workers' Compensation patients had a satisfactory rate of 59%. Twenty patients had open acromioplasty after ASD. Inadequate decompression was noted in 14 of 20 failed patients. In group 2, 86% of the patients were graded as satisfactory according to the Neer criteria, with 14% unsatisfactory, which included the 2 failures. The 2 (9%) of 22 shoulders that failed the ASD went on to further surgical treatment. Average follow-up was 56 months (range, 13 to 78 months). The average American Shoulder and Elbow Society score at follow-up was 90.4. No difference between Workers' Compensation cases and the other cases was seen (P <.7). Finger palpation can help to improve outcomes by allowing the surgeon to assess the adequacy of decompression.

Reliability of radiographic assessment of acromial morphology.

The most widely used radiographic classification system for acromial morphology identifies three distinct acromial shapes: type I (flat), type II (curved), and type III (hooked). The purpose of this study was to measure the interobserver and intraobserver reliability of determinations of acromial morphology as defined by this system. Between 1990 and 1992, one hundred twenty-six supraspinatus outlet radiographs were obtained from 126 patients by technicians from Triangle Orthopaedic Associates in Durham, N.C. Six fellowship-trained shoulder surgeons independently reviewed each radiograph and classified it as type I, II, or III on the basis of established guidelines. Two surgeons classified each film a second time in random order. Analysis of variance was performed to obtain coefficients for interobserver and intraobserver reliability. Consensus ratings were then used to classify the 126 radiographs into consensus type I, consensus type II, or consensus type III groups. Percentages of type I, II, and III individual ratings within each consensus group were determined. The intraobserver reliability coefficient was 0.888, interpreted as good to excellent reliability. The interobserver reliability coefficient was 0.516, interpreted as poor to fair reliability. Of the 126 radiographs, 26 (20.6%) were rated as consensus type I, 76 (60.3%) were rated as consensus type II, and 24 (19.1%) were rated as consensus type III. The reliability of observer ratings was lowest when delineation between acromial types II and III was required. The low interobserver reliability makes comparisons of studies by different authors difficult to interpret and obscures the true incidence of acromial morphologic types. It also questions reported correlations between acromial type and shoulder pathologic conditions. It is concluded that a system that incorporates more objective classification criteria and acknowledges the continuous nature of acromial morphologic types may improve interobserver reliability and validate the system's use in making clinical and surgical judgments.

Comparison of bone contusion seen by MRI in partial and complete tears of the anterior cruciate ligament.

OBJECTIVE: Bone contusions are frequently found in association with complete tears of the anterior cruciate ligament (ACL) and can be a helpful secondary sign in diagnosis. We compare the frequency, location, and significance of bone contusions in complete and partial ACL tears. MATERIALS AND METHODS: Twenty-nine patients with complete and 42 patients with incomplete tears of the ACL were examined by MRI for the presence of accompanying bone contusions within 1 month of injury. RESULTS: Bone contusions were found in 72% of the complete ACL tears but in only 12% of the partial tears. Of the partial ACL tears with accompanying contusions, 80% were high grade injuries that eventually went on to complete rupture within 6 months. Only 16% of the partial ACL injuries without bone contusion progressed to complete rupture at 1-2 year follow-up. There was no difference between the bone contusions of partial and complete tears in terms of general appearance and location. They were predominantly in the lateral compartment (90%) and had a specific predilection for the mid portion of the lateral femoral condyle and the posterior portion of the lateral tibial plateau, often occurring in tandem. CONCLUSION: Bone contusions occur with much less frequency in partial ACL tears than in complete tears but their presence in partial rupture favors a high grade tear that is likely to become complete.

Biomechanical comparison between high tibial osteotomy (HTO) and combined HTO and fibular osteotomy.

The ojectives of this study were to determine the changes in the lateral ligamentous stability of knee joint that occur after performing high tibial osteotomy with and without fibular osteotomy. Utilizing cadaveric specimens, lateral ligamentous stability was assessed by calculating the length of the lateral collateral ligament, and the lateral opening at different flexion angles when varus stress was applied to the tibia. The Polhemus 3-SPACE system was used to collect motion data describing the six-degrees-of-freedom three-dimensional tibiofemoral motions. It was found that the separation distance between the two attachment points of the lateral collateral ligament decreased by an average of 5 mm at all flexion angles after performing a 5-degree valgus high tibial osteotomy. Performing an additional 5-degrees of osteotomy caused this distance to further decrease. It was further found that performing a fibular osteotomy following a 5-degree valgus high tibial osteotomy produced no changes in the length of the lateral collateral ligament. It was also found that the lateral opening increased an average of 5 mm at all flexion angles after performing a 5-degree valgus high tibial osteotomy. Performing a 10-degree osteotomy caused a further increase in the lateral opening. It was further found that performing a fibular osteotomy following a 5-degree valgus high tibial osteotomy caused the lateral opening to return to its original value. That is to say, the fibular osteotomy negated the lateral opening caused by the tibial osteotomy and produced a pattern of lateral opening similar to the one found in the intact knee.

Management of a multiply injured Jehovah's Witness with severe acute anemia.

The refusal of blood products by Jehovah's Witnesses creates ethical and medicolegal dilemmas for the treating physician. Appropriate management involves some understanding of the beliefs of the Jehovah's Witnesses and knowledge of a variety of techniques to minimize blood loss. This case report describes the treatment of a Jehovah's Witness with severe anemia and multiple skeletal injuries. The need to keep blood loss to a minimum influenced the management of this patient.

MRI of suprascapular neuropathy in a weight lifter.

Suprascapular neuropathy results from abnormal compression of the suprascapular nerve, typically at the suprascapular or spinoglenoid notch. This may be produced by either mass effect such as ganglion cyst or by certain repetitive shoulder motions producing wide scapular excursion (e.g., hyperabduction), which causes traction upon the nerve. Certain sports activities such as weight lifting predispose to this type of neuropathy. The clinical presentation is frequently not specific and the patient may be sent for MR evaluation to rule out rotator cuff tear or other more common shoulder abnormalities. This entity should be suspected if MR images demonstrate selective atrophy of the spinatus muscles with a structurally intact rotator cuff.

Post-traumatic synovitis presenting as a mass in the suprapatellar bursa of the knee. MRI appearance.

A lobulated mass in the suprapatellar bursa of the knee is presented with MRI findings simulating the features of focal pigmented villonodular synovitis (PVS). Microscopic examination demonstrated a nonspecific, inflammatory mass of hypertrophied synovium. The MRI features of various forms of synovitis are reviewed from recent literature and differential considerations of a suprapatellar, intrabursal mass are discussed.

Chronic bursitis presenting as a mass in the pes anserine bursa: MR diagnosis.

A case of chronic, nonspecific synovial inflammation presenting as a mass in the pes anserine bursa is demonstrated by MRI. The lesion was well demarcated and surrounded by a low intensity rim. On spin echo images it was homogeneous and of intermediate signal intensity, whereas on T2-weighted images it showed scattered areas of high signal producing a heterogeneous pattern. It is contrasted with a typical example of acute pes anserine bursitis, presenting as simple fluid within the bursa. The differential considerations vary accordingly between the acute and chronic forms of pes anserine bursitis, with the latter requiring differentiation from other forms of synovitis, synovial hemangioma, and synovial sarcoma. The MR features of these entities are reviewed as an aid in differential diagnosis.

Comparison of perioperative morbidity of anterior cruciate ligament autografts versus allografts.

We present a retrospective report of 50 patients (31 autograft and 19 allograft patients) who underwent arthroscopic bone-patellar tendon-bone anterior cruciate ligament (ACL) reconstructions between August 1988 and September 1990. All patients were followed for a minimum of 2 years. The purpose of this study was to analyze each group regarding hospital stay, swelling, thigh atrophy, laxity, strength, endurance, range of motion, patellofemoral symptoms, and complications. We found no statistical difference between autograft or allograft ACL reconstructions with regard to perioperative morbidity.

Results of Judet quadricepsplasty.

Eleven patients (with 12 supracondylar femur fractures) with knee extension contractures were followed for an average of 24.8 months (range 12-45) after Judet quadricepsplasty. An increase in motion of 53 degrees with active postoperative flexion of 91 degrees was noted. There was an average loss of 14 degrees of flexion from maximum intraoperative correction. One patient had an extensor lag of 30 degrees, which did not improve after quadricepsplasty, but no other patients developed an extensor lag, infection, or skin breakdown after the procedure.

MR imaging of the quadriceps tendon: normal layered configuration and its importance in cases of tendon rupture.

OBJECTIVE: The quadriceps tendon is a multilayered structure with separate layers arising from different muscle groups. We examined this layered configuration on MR images to determine if it is relevant in the evaluation of the traumatized quadriceps tendon. MATERIALS AND METHODS: Sagittal and axial T1-weighted MR images of 52 knees with normal tendons were reviewed to determine the number and the muscle origins of these layers. Five knees with traumatized quadriceps tendons were imaged with T1 and T2 weighting to determine the relationship between the layered configuration and the injury. RESULTS: All the normal quadriceps tendons had a laminated appearance with either four (6%), three (56%), or two (30%) layers. In 8%, the laminations were barely perceptible. The site of origin of each layer was consistent, and each favored a given muscle. The superficial layer originated from the posterior fascia of the rectus femoris muscle, and the deep layer originated from the anterior fascia of the midline vastus intermedius muscle. The middle layer(s) arose from the deep fascia separating the vastus medialis and the vastus lateralis muscles from the vastus intermedius muscle. When only two layers were present, the middle layer merged with the superficial and deep layers. In the injured tendon, complete rupture produced transection of all the layers. Incomplete ruptures were seen as focal discontinuities of individual layers; other layers remained intact. CONCLUSION: The existence of a layered configuration of the quadriceps tendon is significant in the MR examination of partial ruptures. It can help not only in detecting and localizing injuries but also in determining appropriate treatment based on the number or thickness of injured layers.

The anterior cruciate ligament-deficient knee with varus alignment. An analysis of gait adaptations and dynamic joint loadings.

Thirty-two patients with an ACL-deficient knee and lower limb varus alignment and 16 healthy controls were analyzed during level walking using a force-plate and optoelectronic system. The forces and moments of the lower limb and knee joint were measured and knee joint loads and ligament tensile forces were calculated using a mathematical model. The majority of patients (20 of 32) had an abnormally high adduction moment at the affected knee. The adduction moment showed a statistically significant correlation to high medial tibiofemoral compartment loads and high lateral soft tissue forces, but not to the degree of varus alignment on standing roentgenograms. Fifteen of 32 knees had abnormally high lateral soft tissue forces. We interpreted these gait findings as indicative of a medial shift in the center of maximal joint pressure and an increase in lateral soft tissue forces to achieve coronal plane stability. Further, there is the likelihood of separation of the lateral tibiofemoral joint and "condylar lift-off" during periods of the stance phase. If this occurs, all of the load-bearing forces would shift to the medial tibiofemoral joint and relatively large tensile forces would occur in the lateral soft tissue restraints. The flexion moment, as related to the quadriceps muscle force, was significantly lower than the control knees in 40% of the involved knees, and the extension moment, as related to the hamstring muscle force, was significantly higher in 50% of the involved knees. We interpret this finding as a gait adaptation tending to diminish quadriceps muscle activity and enhance hamstring muscle activity to provide dynamic anteroposterior stability of the knee joint. The fundamental assumption of this paper is that any combination of conditions leading to higher medial joint forces is associated with factors leading to more rapid degeneration of the medial compartment in patients with ACL deficiency, varus deformity, and lax lateral ligaments.

Effects of tibial rotations on patellar tracking and patello-femoral contact areas.

The object of this study is to determine the effect of tibial rotations on the three-dimensional patello-femoral motions and contact areas during a physiological loading condition, the knee-extension exercise. A commercially available device, the 3-SPACE digitizer and tracker system, was used to collect the motion data, utilizing cadaveric human lower limbs as well as the geometric measurements describing the articular surfaces at the patello-femoral joint. It was found that tibial rotations caused statistically significant differences, at the 0.05 level, in patellar tilt, patellar rotation and patellar medial-lateral shift. It was also found that while the magnitude of the total contact area at a given knee flexion angle did not change significantly with tibial rotations, medial and lateral components of the total contact areas were affected by tibial rotations. Medical femoral contact areas increased with internal tibial rotations at all flexion angles; lateral femoral contact areas increased with external tibial rotations at all flexion angles. This correlates well with the kinematic data since it was found that the patella shifted medially with internal tibial rotations at all flexion angles, and titled more medially near full-extension causing an increase in the medial contact areas and a decrease in the lateral contact areas.

Internal fixation of radial neck fracture in a fracture dislocation of the elbow. A case report.

A 27-year-old manual laborer presented with dislocation of the right elbow, complete separation of the radial head at the neck level, and avulsion of the coronoid process. Closed reduction of the elbow resulted in ulnohumeral instability. As an alternative to silastic implant, the radial head was reduced, internally fixed, and used as a spacer to restore elbow stability. The radial head fracture healed with no sequelae. At two years follow-up examination, the patient had a stable elbow with nearly full range of motion.

MR imaging of the peroneal tunnel.

Fifteen ankles of five male volunteers, five female volunteers, three cadavers, and two patients suspected of injury were imaged. Sagittal localizer scans were obtained through mid- to lateral ankle followed by T1-weighted (echo time 20 ms, repetition time 600 ms) oblique axial sections paralleling the plane of the superior peroneal retinaculum. The anatomical structures seen on magnetic resonance images correlated closely with subsequently frozen and cut cadaver sections. The position of the peroneal tendons could be determined with absolute certainty, the posterior fibular anatomy could be defined, and the retinaculum could be identified in all cases. Though demonstrating considerable variability with respect to thickness, the retinaculum could be seen with sufficient confidence to establish its integrity or lack thereof in most instances. Magnetic resonance should therefore be considered as an aid in the diagnosis of acute peroneal ligament rupture when the clinical picture is not definitive.