David P. Magit

Arthrofibrosis of the knee.

Abstract Better understanding of surgical timing, improved surgical technique, and advanced rehabilitation protocols has led to decreased incidence of motion loss after anterior cruciate ligament injury and reconstruction. However, motion loss from high‐energy, multiligament injuries continues to compromise functional outcome. Prevention, consisting of control of inflammation and early motion, remains the key element in avoiding motion loss. However, certain techniques, such as manipulation under anesthesia in conjunction with arthroscopic lysis of adhesions, are reliable treatment options. Open surgical débridement is rarely necessary and should be considered only as a salvage procedure. A greater understanding of the pathogenesis of arthrofibrosis and related inflammatory mediators may result in novel therapies for treating the patient with motion loss.

Partial-thickness rotator cuff tears.

&NA; Partial‐thickness rotator cuff tears are not a single entity; rather, they represent a spectrum of disease states. Although often asymptomatic, they can be significantly disabling. Overhead throwing athletes with partial‐thickness rotator cuff tears differ with respect to etiology, goals, and treatment from older, nonathlete patients with degenerative tears. Pathogenesis of degenerative partial‐thickness tears is multifactorial, with evidence of intrinsic and extrinsic factors playing key roles. Diagnosis of partial‐thickness rotator cuff tears should be based on the patients symptoms together with magnetic resonance imaging studies. Conservative treatment is successful in most patients. Surgery generally is considered for patients with symptoms of sufficient duration and intensity. The role of acromioplasty has not been clearly delineated, but it should be considered when there is evidence of extrinsic causation for the partial‐thickness rotator cuff tear.

Healos/recombinant human growth and differentiation factor-5 induces posterolateral lumbar fusion in a New Zealand white rabbit model.

Study Design. Posterolateral lumbar spine fusions in New Zealand white rabbits. Objective. To evaluate the efficacy of recombinant human growth and differentiation factor-5 (rhGDF-5) lyophilized to a Healos carrier (cross-linked type I collagen with hydroxyapatite coating; DePuy Spine, Inc., Raynham, MA) in inducing fusion. Summary of Background Data. Bone graft substitutes have become an area of considerable interest. rhGDF-5 is one such product. Limited lumbar preclinical studies have been performed with this product. Methods. Single-level, intertransverse process fusions were performed in 67 rabbits using iliac crest autograft (n = 13), Healos alone (n = 13), or 0.5, 1.0, or 1.5 mg/cc rhGDF-5 lyophilized to Healos (n = 13 per group). At 8 weeks, the rabbits were euthanized. Fusion masses were assessed. Results. There were 2 animals (3%) lost to complication. Manual palpation revealed fusion rates for autograft of 38% (5/13), Healos alone of 0% (0/13), and each of the Healos/rhGDF-5 groups of 100% (13/13). Histologic analyses were 95% sensitive and 95% specific for confirming fusion. Histologic differences were found among the treatment groups. Conclusions. In this rabbit fusion model, Healos/rhGDF-5 induced fusion in 100% of the rabbits studied. This rate was significantly higher than the fusion rate induced by autograft (38%). Overall, these results support continued research of Healos/rhGDF-5 as a potential bone graft alternative.

Questionnaire study of neuromonitoring availability and usage for spine surgery.

Study Design Questionnaire study presented to practicing spine surgeons. Objective To evaluate surgeon preference and availability of selected electrophysiologic neuromonitoring for different spine surgeries. Summary of Background Data Maximizing the safety of spinal procedures and limiting potential iatrogenic neurologic injury has made intraoperative neuromonitoring an attractive option. Methods We distributed a questionnaire to 180 orthopedic spine surgeons and neurosurgeons at a clinically oriented spine meeting asking surgeon preference and availability of various types of intraoperative neuromonitoring modalities for different types of surgical procedures. Demographic data were also gathered. Results Somatosensory evoked potentials (SSEPs) were the most available neuromonitoring modality, followed by electromyographies and motor-evoked potentials. In both anterior and posterior cervical surgery, SSEPs were the most preferred modality. MEPs were frequently preferred in myelopathic cervical cases. Almost 70% preferred some neuromonitoring for anterior thoracic/thoracolumbar cases and 55% for posterior thoracic/thoracolumbar cases. Surgeon satisfaction was related to the number of available neuromonitoring modalities. No significant differences were found between orthopedist and neurosurgeon preferences. Fellowship-trained surgeons were more likely to use neuromonitoring for specific indications. Conclusions SSEPs remains the most widely available and preferred type of neuromonitoring for spine surgeons. The type of case and neurologic status of patient (eg, presence of myelopathy) affects these choices. Surgeons were more satisfied with greater neuromonitoring availability, and were more likely to use neuromonitoring if they had a fellowship background.

In vivo Comparison of Changes in Glenohumeral Translation after Arthroscopic Capsulolabral Reconstructions

Background The objective of this study was to quantify anteroposterior glenohumeral translation of patients undergoing arthroscopic capsulolabral repairs using cutaneous electromagnetic position sensors. Hypothesis Anteroposterior translation will be restored after arthroscopic capsulolabral repairs to values similar to the contralateral or uninjured shoulder. Study Design Cohort study; Level of evidence, 2. Methods With use of an electromagnetic tracking system, preoperative anteroposterior translation was measured in the injured and uninvolved shoulders of 32 patients with a diagnosis of glenohumeral labral tears. Testing was done with patients placed in the supine position with the arm suspended in 90° of abduction and neutral rotation. The American Shoulder and Elbow Society index and range of motion were also measured. Patients with capsulolabral injuries requiring arthroscopic repair were reexamined at 3 and 6 months postoperatively. Results In patients with anteroinferior/posteroinferior capsulolabral repairs, glenohumeral translation at 3 and 6 months postoperative (P < .0001) was significantly decreased compared with preoperative values (P = .0007) and the uninvolved side (preoperative, P = .04; postoperative, P = .002). In patients with superior capsulolabral (superior labral anterior-posterior) repairs, the mean glenohumeral translation at 3 and 6 months postoperative was decreased significantly compared with the preoperative value; however, no significant differences were found between the uninvolved side (preoperative, P = .5) and the operative shoulder (postoperative, P = .2). By 6-month follow-up, no significant difference existed in external rotation when compared with preoperative values for either repair group. Conclusion Arthroscopic superior capsulolabral reconstructions successfully restored anteroposterior translation. However, arthroscopic capsulolabral techniques for treating recurrent anterior or posterior instability resulted in decreased anteroposterior translation compared to the uninvolved side while restoring external rotation.

Comparison of Cutaneous and Transosseous Electromagnetic Position Sensors in the Assessment of Tibial Rotation in a Cadaveric Model

Background Recent studies have highlighted the growing interest in validating anatomic anterior cruciate ligament reconstructions. A simple method of measuring tibial rotation is necessary to provide an objective clinical assessment of restoration of normal knee kinematics after various anterior cruciate ligament reconstructive techniques. Objective To validate a new method of measuring tibial rotation by comparing cutaneous with transosseous electromagnetic position sensors during a simulated standard knee examination. Study Design Controlled laboratory study. Methods Eight thawed, fresh-frozen cadaveric knee specimens with skin and soft tissues preserved were mounted on the femoral side in neutral rotation by a rigid clamp, allowing 6 degrees of freedom of the knee joint. With the knee fixed at 30° of flexion, a series of maximal manual internal and external tibial rotations were performed and measured with an electromagnetic tracking system that measures 6 degrees of freedom in a Cartesian coordinate system. During each series of measurements, a cutaneous transmitter was fixed overlying the tibial tuberosity. Simultaneously, a second transducer was rigidly fixed to a transosseous pin placed just distal to the tibial tubercle. Measurements were repeated at 90° of flexion. Differences in measurements were assessed. Results No significant differences were found with maximal internal and external rotation between cutaneous and transosseous measurements at 30° of knee flexion (13.0° vs 14.5°, P = .4) or at 90° of flexion (11.2° vs 12.9°, P = .5). Correlation (R) between cutaneous and transosseous measurements at 30° was .97 (P = .00009) and at 90° was .99 (P < .00001). The accuracy of cutaneous measurements using transosseous as the known was 1.6° ± 1.3°. Repeatability of cutaneous measurements was 0.8° ± 0.4°. The repeatability of transosseous measurements was 1.0° ± 0.5°. Conclusion No significant differences were found at either 30° or 90° of flexion when measuring tibial rotation using cutaneous versus transosseous electromagnetic position sensors. Clinical Relevance The ability to measure knee rotation using cutaneous electromagnetic position sensors represents a promising new method for assessing various clinical conditions and surgical outcomes.

Sterilization wrap inspections do not adequately evaluate instrument sterility

Orthopaedic procedures rely on strict sterilization techniques to prevent surgical site infections. Surgical instrument trays are wrapped for sterilization, and these wraps routinely are inspected by operating room personnel to evaluate for breaches before using the contained instruments. The sensitivity of this practice for detecting wrap defects has not been established. We divided 90 sterilization wraps into groups with no defect and with six sizes of defects ranging from 1.1 to 10.0 mm in diameter. Puncture-type defects were created using nails of known diameter. All wraps were evaluated by medical personnel for evidence of a breach. Detection rates ranged from 6.7% to 96.7% from the smallest to largest defects, respectively. The potential for bacterial transmission through wrap defects also was evaluated, and contaminated nails of the smallest size transmitted bacterial contaminants through the wrap during the creation of puncture defects. Thus, substantial perforations in sterilization wraps frequently are missed when evaluated with commonly used techniques. Defects with a diameter approximately that of a pencil (6.7 mm) were missed 18% of the time, although contamination can be transmitted by a nail with the diameter of a pin (1.1 mm). These results raise questions about a common screening method.

Intramedullary Nailing for the Management of Intertrochanteric and Subtrochanteric Geriatric Fractures

The number of hip fractures worldwide has been estimated to increase from 1.22 million in 1990 to an estimated 2.6 million in 2006.1,19 With union rates greater than 95%, the sliding hip screw and plate construct represents the current standard of treatment for peritrochanteric femur fractures. However, complications associated with sliding hip screw and plate systems have generated a considerable amount of interest in the use of intramedullary implants for these common fractures. Limited open techniques offer the potential for less blood loss and soft tissue insult, thus decreasing the potential for perioperative complications while allowing rapid mobilization and return to preinjury function. Intramedullary implants also represent biomechanical improvements from conventional sliding hip screw and side plate constructs, theoretically reducing the incidence of screw cutout, excess collapse at the fracture site, and implant failure. This article discusses the rationale for treatment with the intramedullary hip screw over the sliding hip screw and side plate, describes the techniques of reduction as well as percutaneous adjuncts to treatment, examines some of the special situations that strongly support its use, and reviews the early and recent outcomes of this treatment.