John M. Marzo

Effects of Medial Meniscus Posterior Horn Avulsion and Repair on Tibiofemoral Contact Area and Peak Contact Pressure with Clinical Implications

Background Avulsion of the posterior horn attachment of the medial meniscus can compromise load-bearing ability, produce meniscus extrusion, and result in tibiofemoral joint-space narrowing, articular cartilage damage, and osteoarthritis. Hypothesis Avulsion of the posterior horn of the medial meniscus will increase peak contact pressure and decrease contact area in the medial compartment of the knee, and posterior horn repair will restore contact area and peak contact pressures to values of the control knee. Study Design Controlled laboratory study. Methods Eight fresh-frozen human cadaveric knees had tibiofemoral peak contact pressures and contact area measured in the control state. The posterior horn of the medial meniscus was avulsed from its insertion and knees were retested. The meniscal avulsion was repaired by suture through a transosseous tunnel and the knees were tested a third time. Results Avulsion of the posterior horn attachment of the medial meniscus resulted in a significant increase in medial joint peak contact pressure (from 3841 kPa to 5084 kPa) and a significant decrease in contact area (from 594 mm2 to 474 mm2). Repair of the avulsion resulted in restoration of the loading profiles to values equal to the control knee, with values of 3551 kPa for peak pressure and 592 mm2 for contact area. Conclusion Posterior horn medial meniscal root avulsion leads to deleterious alteration of the loading profiles of the medial joint compartment and results in loss of hoop stress resistance, meniscus extrusion, abnormal loading of the joint, and early knee medial-compartment degenerative changes. Clinical Relevance The repair technique described restores the ability of the medial meniscus to absorb hoop stress and eliminate joint-space narrowing, possibly decreasing the risk of degenerative disease.

Intraarticular fibrous nodule as a cause of loss of extension following anterior cruciate ligament reconstruction.

Loss of motion is a well-known complication following anterior cruciate ligament (ACL) reconstruction. We have found that loss of extension is more disabling than loss of flexion, and is a more common problem following arthroscopic assisted ACL reconstruction. We are reporting on a group of 21 patients who have developed restricted knee extension following ACL reconstruction utilizing either the central one-third of the patellar ligament or the hamstring tendons as an autogenous graft. The patients presented at an average of 4 months postoperatively with a clinical syndrome of loss of extension associated with pain at terminal extension, crepitus, and grinding with attempted extension beyond their limit. The consistent finding at arthroscopy was a fibrous nodule occupying the intercondylar notch, varying in size from 1 x 1 to 2 x 3 cm, and presenting a mechanical block to full extension. It appears that anterior placement of the graft, particularly on the tibia, results in injury to the graft and subsequent nodule formation. Removal of the nodule resulted in improvement of an average preoperative loss of extension of 11 degrees, to 3 degrees at surgery, and 0 degrees at 1 year follow-up. The average side-to-side difference in terminal extension at final examination, using the uninvolved limb for comparison, was 3 degrees. Histology was available for review on 19 of the 21 patients operated on. The consistent microscopic finding within the nodule was the presence of disorganized dense fibroconnective tissue that, with time, underwent modulation to fibrocartilage. It is postulated that this occurs in response to compressive loading of the nodule.

The use of systemic hypothermia for the treatment of an acute cervical spinal cord injury in a professional football player.

Study Design. Case Report. Objective. We will describe the injury and clinical course of an NFL Football player who sustained a complete spinal cord injury and was treated with conventional care in addition to modest systemic hypothermia. Summary of Background Data. Systemically induced moderate hypothermia is a potentially neuroprotective intervention in acute spinal cord injury. However, case descriptions of human patients receiving systemic hypothermia after spinal cord injuries are lacking in the literature. Methods. Here, we present the case of a National Football League player who sustained a complete (ASIA A) spinal cord injury from a C3/4 fracture dislocation. Moderate systemic hypothermia was instituted immediately after his injury, in addition to standard medical/surgical treatment, including, surgical decompression and intravenous methylprednisolone. Results. The patient experienced significant and rapid neurologic improvement, and within weeks of his injury was walking with harness assistance. Since that time, the patient has continued to make significant progress in his rehabilitation (now ASIA D). Conclusion. The extent to which this hypothermia contributed to his neurologic recovery is difficult to determine. It is hoped that this case will draw attention to the need for further preclinical and clinical studies to elucidate the role of hypothermia in acute spinal cord injury. Until these studies are completed, it is impossible to advocate for systemic hypothermia as a standard of care.

Minimum 10-Year Follow-up of Arthroscopic Intra-articular Bankart Repair Using Bioabsorbable Tacks

Background: There are few long-term studies evaluating functional outcomes and rates of arthrosis after arthroscopic Bankart repair with bioabsorbable tacks. Purpose: We evaluated the clinical and radiographic results of arthroscopic Bankart repair using intra-articular bioabsorbable tacks at a minimum of 10 years’ follow-up. Study Design: Case series; Level of evidence, 4. Methods: Thirty-two consecutive patients were retrospectively identified. Twenty patients (63%) were evaluated at a mean follow-up of 13.5 years (range, 10.75-17.5 years) and average age of 43 years (range, 28-73 years). The surgical shoulder (SS) was compared with a healthy control shoulder (CS) in 15 of 20 patients. Outcome tools included the Western Ontario Shoulder Instability Index (WOSI) and Disabilities of the Shoulder, Arm, and Hand (DASH). Blinded, independent evaluators performed physical examinations and reviewed radiographs. Results: Thirteen patients (65%) had stable shoulders, 5 of 7 (25%) failed by dislocation, and 2 of 7 (10%) failed by signs of anterior instability on examination. Three patients underwent revision stabilization surgery. Average time to failure was 4.2 years (range, 0.25-14.7 years). Average WOSI and DASH scores were 80% and 7.3, respectively. The CS faired better than SS in WOSI scores (97% vs 83%, respectively; P = .008), main DASH scores (0.39 vs 6.79, respectively; P = .024), and the DASH sports module (0.00 vs 10.94, respectively; P = .043). Patients lost 5.9° of passive forward flexion (P = .031) and 4.3° of passive external rotation (P = .001). Forty percent returned to their preoperative sports level. Higher grades of arthrosis were seen in the SS (20% absent, 40% mild, 25% moderate, and 15% severe) versus CS (P = .002). Conclusion: At long-term follow-up, 65% of patients treated with an arthroscopic Bankart repair using bioabsorbable tacks had a well-functioning, stable shoulder. Disability scores were greatest with sports; however, the majority of patients had well-preserved ranges of motion and good functional WOSI scores. Despite this, 40% had evidence of moderate to severe glenohumeral arthrosis.

Factors Associated With Meniscal Tears and Chondral Lesions in Patients Undergoing Anterior Cruciate Ligament Reconstruction A Prospective Study

Background: Increased time from anterior cruciate ligament (ACL) injury to surgery is known to be associated with increased medial meniscal tears. Few studies have examined the predictors of meniscal tears and chondral lesions, including instability episodes. Purpose: To examine the predictors of meniscal tears and chondral injuries in patients undergoing ACL reconstruction. Study Design: Case-control study; Level of evidence, 3. Methods: Data were collected prospectively from 541 patients undergoing ACL reconstruction. Logistic regression was used to calculate adjusted odds ratios and 95% confidence intervals for predictors of meniscal tears, tear management, and chondral injuries. Predictors included age, sex, body mass index (25-29.99 and ≥30 vs ≤24.99 kg/m2), mechanism (contact vs noncontact) and type (high-impact sports [basketball, football, soccer, and skiing] and other sports vs not sports related) of injury, interval from injury to surgery (≤6 vs >6 weeks and ≤12 vs >12 weeks), and instability episodes (vs none). Results: A total of 211 lateral meniscal tears (35.3% untreated, 48.3% meniscectomized, 16.4% repaired), 197 medial meniscal tears (25% untreated, 52% meniscectomized, 23% repaired), and 82 chondral injuries occurred. Age predicted chondral injuries. Male sex predicted more lateral meniscal tears overall, untreated lateral tears, and lateral meniscectomies as well as predicting medial meniscal tears overall and medial meniscectomies. Obesity predicted more chondral injuries. Sports-related injuries predicted fewer medial meniscal tears overall and medial meniscectomies. Injuries ≤6 weeks from surgery predicted more lateral meniscal repairs but fewer medial meniscectomies. Injuries ≤12 weeks from surgery predicted more chondral injuries. More instability episodes predicted medial meniscal tears overall, untreated medial tears, medial meniscectomies, and medial repairs. Conclusion: Male sex predicted lateral meniscal tears and management. Male sex, sports, injuries ≤6 weeks from surgery, and preoperative episodes of instability predicted medial meniscal tears and management. Age predicted chondral injuries. This was one of the first studies to examine the number of instability episodes as a predictor of an intra-articular injury.

Effects of medial meniscal posterior horn avulsion and repair on meniscal displacement

Medial meniscal posterior root avulsion (MMRA) leads to deleterious alteration of medial joint compartment loading profiles and increased risk of medial degenerative changes. Surgical repair restores more normal biomechanics to the knee. Our hypothesis is that MMRA will cause medial meniscal (MM) extrusion and gap formation between the root attachment site and MM. Meniscal root repair will restore the ability of the meniscus to resist extrusion, and reduce gap formation at the defect. Seven fresh frozen human cadaveric knees were dissected and mechanically loaded using a servo-hydraulic load frame (MTS ®) with 0 and 1800 N. The knees were tested under three conditions: native, avulsed, and repaired. Four measurements were obtained: meniscal displacement anteriorly, medially, posteriorly, and gap distance between the root attachment site and MM after transection and repair. The medial displacement of the avulsed MM (3.28 mm) was significantly greater (p < 0.001) than the native knee (1.60mm) and repaired knee (1.46 mm). Gap formation is significantly larger in the avulsed compared to repaired state at 0 (p < 0.02) and 1800N (p < 0.02) and also larger with loading in both avulsed (p < 0.05) and repaired (p < 0.02) conditions. Therefore, MMRA results in MM extrusion from the joint and gap formation between the MM root and the MM. Subsequent surgical repair reduces meniscal displacement and gap formation at the defect.

Intradural connections between adjacent cervical spinal roots.

It is not always possible to localize the level of cervical pathology accurately on the basis of clinical signs and symptoms. Intradural intersegmental connections between sensory rootlets occur frequently in the cervical region and have been shown to be clinically and surgically significant. Similar connections between motor rootlets also have been noticed, but their incidence was not reported. Fifty-four human cervical spines were dissected to investigate the incidence of both types of connections. Fifty-three of the 54 specimens had posterior rootlet connections, and nine of the 54 had anterior connections. The preponderant pattern (85%) was for a peripheral dorsal or ventral rootlet to join the central portion of the next rostral or caudal root, and for the two to pass together into the spinal cord. Six distinct patterns were recognized, and a classification system is proposed. These connections may provide a pathway for overlap of sensory dermatomes and motor innervation of the neck and upper extremity. Our observations imply that when a cervical nerve root is injured, small segments of an adjacent root may be equally affected, and the process may be clinically localized one segment higher or lower than it actually is.

Ganglion cyst of the shoulder associated with a glenoid labral tear and symptomatic glenohumeral instability : A case report

Shoulder pain may be caused by a variety of abnormalities including glenohumeral instability, rotator cuff disease, cervical radiculopathy, nerve entrapment syndromes, neoplasm, tendinitis, adhesive capsulitis, trauma, and degenerative disease of any one of the joints about the shoulder.1, 13, 16 Patients experiencing entrapment neuropathy of the suprascapular nerve usually complain of shoulder pain.21 Symptoms involve the infraspinatus muscle if the entrapment takes place at the spinoglenoid notch, or the supraspinatus and infraspinatus muscles if the lesion is at the suprascapular notch. 3,5,22,24,30 Mass lesions such as ganglion cysts are a common cause of suprascapular nerve entrapment. 8,12,17,18,25 Glenoid labral abnormalities, including acute tears and degenerative changes, are associated with glenohumeral instability.4,9 There is evidence that periarticular abnormalities in other areas of the body may lead to the leakage of synovial fluid and the formation of so-called ganglion cystS.7,1l,15,20 We report a case of ganglion cyst of the shoulder associated with a posterior glenoid labral tear and glenohumeral instability.

A Prospective Study of the Association Between Bone Contusion and Intra-articular Injuries Associated With Acute Anterior Cruciate Ligament Tear

Background: Bone bruising, commonly found on magnetic resonance imaging (MRI) after anterior cruciate ligament (ACL) injury, may be associated with intra-articular injuries, but little is known about this association. Purpose: To examine demographic factors and intra-articular injuries associated with bone bruising in patients undergoing ACL reconstruction. Study Design: Case-control study; Level of evidence, 3. Methods: Patients with ACL injury who had an MRI within 6 weeks and arthroscopy within 3 months of injury were included in this prospective study (N = 171). Presence and severity of bone bruising were determined from preoperative MRIs for each anatomic site: lateral femoral condyle (LFC), lateral tibial plateau (LTP), medial femoral condyle (MFC), and medial tibial plateau (MTP). Multiple logistic regression was used to calculate adjusted odds ratios (OR) and 95% confidence intervals (CI) for predictors of bruising and associations between bruising and intra-articular injuries found during arthroscopy. Outcomes included the presence of bruising and severity of lateral bruising (mild, moderate, severe vs none/minimal bruising). Results: Frequencies of bone bruising were as follows: 85% LTP, 77% LFC, 26% MTP, and 6% MFC. Patient age between 18 and 28 years (OR, 0.27; 95% CI, 0.09-0.82) and 29 years and older (OR, 0.18; 95% CI, 0.05-0.61) predicted less LFC bruising compared with patients aged 17 years and younger. Age (18-28 years: OR, 0.15; 95% CI, 0.03-0.66; ≥29 years: OR, 0.10; 95% CI, 0.02-0.68) and contact injuries (OR, 0.17; 95% CI, 0.04-0.78) predicted less moderate LFC bruising. Male sex predicted mild (OR, 6.16; 95% CI, 1.44-26.43), moderate (OR, 8.98; 95% CI, 1.96-41.19), and severe (OR, 15.66; 95% CI, 3.19-76.92) LFC bruising. Male sex also predicted mild LTP bruising (OR, 0.19; 95% CI, 0.05-0.83), and contact injuries predicted severe LTP bruising (OR, 5.01; 95% CI, 1.21-20.67). LFC bruising (OR, 2.57; 95% CI, 1.04-6.32) and LTP bruising (OR, 3.13; 95% CI, 1.06-9.23) were associated with lateral meniscal tears. Moderate (OR, 8.14; 95% CI, 1.93-34.27) and severe (OR, 15.30; 95% CI, 2.34-100.10) LTP bruising was associated with medial meniscal tears. MFC bruising and MTP bruising were not associated with any predictors or intra-articular injuries. Conclusion: Bone bruising is more common and severe in young men, and lateral bone bruising is associated with lateral meniscal tears. Medial meniscal tears are associated with increased severity of LTP bruising.

A safe zone for resection of the medial end of the clavicle

Medial clavicle resection is indicated when symptoms of sternoclavicular instability or degeneration remain disabling despite nonoperative management. Preservation or reconstruction of the costoclavicular ligament (rhomboid ligament) is essential to prevent subsequent instability of the remainder of the medial clavicle. Eighty-six cadaveric sternoclavicular joints were dissected to determine the distance (safe resection length [SRL]) from the inferior articular surface of the medial end of the clavicle to the most medial insertion of the costoclavicular ligament (rhomboid ligament). The mean SRL was 1.2 +/- 0.3 cm in men and 1.0 +/- 0.2 cm in women. Resection of 1.0 cm of the medial clavicle would result in no or minimal disruption of the costoclavicular ligament in 84% of men, and resection of 0.9 cm of the medial clavicle would result in no or minimal disruption of the costoclavicular ligament in 89% of women. We recommend that these amounts be used as a guide to safe resection of the medial clavicle but that the costoclavicular ligament be exposed to allow certainty of preservation.