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R C Schenck

Publications and source records attributed to R C Schenck.

At least 19 recordsLinked to original sources
PubMed2001

Complications of metallic suture anchors in shoulder surgery: A report of 8 cases.

PURPOSE: Metallic suture anchors are widely used in open and arthroscopic operations about the shoulder. We report the cases of 8 patients who were referred to our institution with complications following shoulder surgery in which metallic suture anchors were used. TYPE OF STUDY: Retrospective case series. METHODS: There were 7 male patients and 1 female patient with an average age of 36 years (range, 18 to 76 years). The initial operation was open anterior reconstruction for anterior instability of the glenohumeral joint in 5 patients, open rotator cuff tear repair in 2 patients, and an open posterior capsular reconstruction for posterior instability in 1 patient. All patients were referred for evaluation after a failed index reconstructive procedure. RESULTS: On average, 5.5 suture anchors (range, 3 to 8) per shoulder were used. Of 4 patients undergoing reconstruction with glenoid anchors only, 3 patients had an extraosseously positioned device. In this subset of glenoid-sided reconstructions, when more than 3 anchors were used, at least 1 anchor was inserted in an extraosseous position. In 2 of 3 patients with isolated humeral anchors, there was evidence of migration over time (1 intra-articular, 2 bursal). Three patients (38%) developed severe articular damage that was directly caused by a loose or intra-articular metal suture anchor. One patient developed a wound infection after reconstructive surgery. In all 8 patients, the index procedure failed and required subsequent surgery. CONCLUSIONS: The use of metallic suture anchors about the shoulder is commonplace and useful, but, as with other hardware used about the shoulder, there are significant risks if the anchors are improperly placed or if the index procedure fails.

Adult↗
PubMed2000

Argument against use of food additives for osteoarthritis of the hip.

Food additives and other forms of alternative medicines have been embraced by the general public. Some of these compounds including glucosamine and chondroitin sulfate have shown efficacy in relieving pain associated with osteoarthritis. However, evidence is limited concerning the chondroprotective ability of these agents. More controlled studies and basic research is necessary to evaluate these claims especially because these compounds are not under regulatory control.

Complementary Therapies↗
PubMed1999

Knee dislocations.

Explore the source record for details and available documents.

Anterior Cruciate Ligament Injuries↗
PubMed1998

Biomechanical topography of human articular cartilage in the first metatarsophalangeal joint.

The objective of this study was to provide a map of cartilage biomechanical properties, thickness, and histomorphometric characteristics in the human, cadaveric first metatarsophangeal joint, to determine if normal articular cartilage was predisposed topographically to biomechanical mismatches in articulating surfaces. Cartilage intrinsic material properties and thickness were obtained from seven pairs of human, freshly frozen, cadaveric, metatarsophalangeal joints using an automated creep indentation apparatus under conditions of biphasic creep. Eight sites were tested: four on the metatarsal head, two on the proximal phalanx base, and one on each sesamoid bone to obtain the aggregate modulus, Poisson's ratio, permeability, shear modulus, and thickness. Cartilage in the lateral phalanx site of the left metatarsal head had the largest aggregate modulus (1.34 MPa), whereas the softest tissue was found in the right medial sesamoid (0.63 MPa). The medial phalanx region of the right joint was the most permeable (4.56 x 10(-15) meter4/Newton-second), whereas the medial sesamoid articulation of the metatarsal head of the left joint was the least permeable (1.26 x 10(-15) meter4/Newton-second). Material properties and thickness are indicative of the tissue's functional environment. The lack of mismatches in cartilage biomechanical properties of the articulating surfaces found in this study may be supportive of clinical observations that early degenerative changes, in the absence of traumatic events, do not occur at the selected test sites in the human first metatarsophalangeal joint.

Adolescent↗
PubMed1997

Porous-coated titanium implant impregnated with a biodegradable protein delivery system.

Tissue ingrowth into porous-coated orthopedic and dental implants is commonly used as a means to achieve long-term fixation of these prostheses. However, the degree of tissue ingrowth is often inadequate and inconsistent. If the pores of these implants are impregnated with a controlled drug release system delivering relevant growth factors, then it might be possible to stimulate more tissue ingrowth. The present study introduces such a system based on biodegradable polymers and investigates its protein release profile and polymer degradation characteristics. Porous coated titanium implants were impregnated with a mixture of a 50%-50% polylactic acid-polyglycolic acid copolymer and a model protein, soybean trypsin inhibitor. Control implants contained only the polymer and no protein. The implants were subjected to hydrolytic degradation in phosphate buffered saline at 37 degrees C for periods of 3, 6, and 11 weeks. The protein release and the mass and molecular weight of the polymer were monitored. The results indicate that the protein is released in three distinct phases and the polymer loses almost all its mass and molecular weight by 11 weeks. There was a significant difference in the polymer degradation characteristics between the control and test implants, which might be the result of some complex polymer-protein interactions.

Biocompatible Materials↗
PubMed1997

A prospective outcome study of rehabilitation programs and anterior cruciate ligament reconstruction.

We evaluated the outcome of and compared two rehabilitation programs (clinic-based versus home) after a mid-third patellar autograft reconstruction of the anterior cruciate ligament. Thirty-seven patients (28 male, 9 female; average age, 24.1 years) completed the study. Fifteen of these patients received clinic-based rehabilitation (three visits per week for 6 weeks prescribed), and 22 patients received home-based physical therapy (number of visits determined by patient response). Knee ROM, Lysholm, Visual Analogy Scale, (VAS) pain rating, hop test, KT-1000, and Sickness Impact Profile (SIP) were evaluated preoperatively and postoperatively. All patients reported good satisfaction with the function of their knee at average follow-up of 21.6 months (range, 12 to 48). Patients managed by home rehabilitation averaged 2.85 visits as compared with 14.2 for clinic-centered patient (P < .05). There were no differences in functional or subjective outcomes in the different postoperative rehabilitation regimens, with both groups reporting high satisfaction and improved quality of life. Cost savings in the home rehabilitation group were significant.

Adult↗
PubMed1997

Morphology of the axillary nerve in an anteroinferior shoulder arthroscopy portal.

An anteroinferior portal can be safely used in arthroscopic shoulder surgery but requires an in-depth knowledge of axillary nerve anatomy. The purpose of this report is to present the qualitative and spatial anatomy of the axillary nerve and to describe patterns of arborization that may affect safe anteroinferior arthroscopic portal placement. Measurements were taken in 42 embalmed cadaveric shoulders (20 male, 22 female). The distance from the acromioclavicular (AC) joint to the axillary nerve averaged 7.90 cm (range, 7.2 to 9.1 cm) in males and 6.37 cm (range, 5.2 to 8.1 cm) in females. We describe the axillary nerve index (distance of nerve from the AC joint/length of deltoid from AC joint) which can be used to predict the location of the axillary nerve along the anterior clavicular line (ACL). The axillary nerve index averaged 0.48 (range, 0.42 to 0.57) in males and 0.41 (range, 0.31 to 0.57) in females. Four types of morphology were noted in the axillary nerve: (1) main trunk with superior and inferior branches, (2) main trunk with superior branches, (3) main trunk with inferior branches, and (4) main trunk only. Our work supports the traditional operable safe zone for the axillary nerve.

Aged↗
PubMed1997

Femoral-sided fracture-dislocation of the knee.

OBJECTIVE: To document a previously undescribed fracture-dislocation of the knee that involves a femoral condyle and associated ligaments yet spares the tibial joint surface. DESIGN: Retrospective. SETTING: University. PATIENTS: Four cases of fracture-dislocation of the knee that involve ligamentous injury and fracture of the femoral condyle(s). RESULTS: At a minimum two-year follow-up (average 28.8 months, range 26 to 37 months), overall functional outcome is only fair to good in this injury pattern. The Lysholm knee rating averaged 60 (range 39 to 74) and KT-1000 I-N testing averaged three millimeters at thirty pounds. CONCLUSION: Despite treatment of this fracture-dislocation with internal fixation of the femoral condyle(s) and repair of the ligament(s), functional deficits occur in this severe knee injury patterns.

Adult↗
PubMed1997

Management of shoulder dysfunction with an alternative model of orthopaedic physical therapy intervention: a case report.

One common approach to patient care in dealing with many musculoskeletal dysfunctions involves two to three patient visits to physical therapy per week over a period of weeks. Some patients may benefit from an alternative, graduated treatment model emphasizing a minimal number of office visits and focusing on intensive patient education, home program therapeutic exercise, and specific manual interventions. Patient education focuses on home program compliance and empowerment of the patient by adjusting office visits as needed based on patient progress rather than multiple patient contacts in the first weeks. This emphasis may improve long-term patient compliance by preventing the development of an external locus of control in which the patient is dependent upon the therapist for management of his/her condition. This case study is an example of the use of this alternative treatment model for the resolution of impingement syndrome and adhesive capsulitis in a 53-year-old female. A comprehensive program of patient education and home exercise was initiated during the first visit. Joint mobilization and active exercise were performed at each subsequent visit. The patient was seen a total of six visits over a period of approximately 10 1/2 weeks, followed up via telephone at 1 month after the last treatment and reexamined after 1 year. The objective exam revealed no abnormalities after the last visit or after 1 year. The patient subjectively reported compliance with the home program for 6 months after the last visit. This model of patient care was successful for the patient described in this case study. The treatment approach may have contributed to the development of an internal locus of control by allowing the patient to be as actively involved as possible in the treatment of her condition. In addition, this approach is timely when one considers current reimbursement systems. Though successful with this patient, this graduated treatment model is not intended to be applicable to every patient with this diagnosis.

Bursitis↗
PubMed1996

Clinical and anatomic considerations in the use of a new anterior inferior subaxillary nerve arthroscopy portal.

The axillary nerve has been an obstacle to safety creating bone tunnels for arthroscopic rotator cuff repair. Anatomic dissections of 42 cadaver shoulders have defined anatomic relationships that have allowed the authors to develop a safe arthroscopy portal distal to the axillary nerve. The senior author (SSB) has used this portal without complications in achieving arthroscopic transosseous rotator cuff repair. This portal allows the proper angle of approach to locate the distal hole of the tunnel in strong cortical bone.

Arthroscopy↗
PubMed1996

Arterial injuries in orthopaedics: the posteromedial approach for vascular control about the knee.

Combined orthopaedic and vascular injuries are becoming more common owing to an increasing incidence of high-energy trauma and gunshot wounds. We present our experience using the posteromedial approach in treating eight orthopaedic patients with popliteal arterial injuries. All patients underwent popliteal exploration by a vascular surgeon through a posteromedial approach (releasing the pes anserinus and the medial gastrocnemius). The arterial injuries were reconstructed in five patients using a reverse saphenous vein graft and directly repaired in three patients. Two patients had delayed healing of their incisions as a result of the original injury. There were no neural injuries. The posteromedial approach is extensile and utilitarian, and it represents the exposure of choice for arterial injuries about the knee.

Adolescent↗
PubMed1996

Successful revascularization of a partially avulsed foot in a 6-year-old child.

The foot of a 6-year-old child was revascularized successfully following an avulsion and partial amputation through the tibiotalar joint. Partial degloving had disrupted the anterior and posterior tibial arteries with resultant ischemia. We excised the entire damaged segment of the posterior tibial artery and performed a reverse saphenous vein graft, end-to-end reconstruction of the defect. Peroneal and tibial nerve function returned within 5 months. Four years later, the patient has regained full, painless range of motion and normal strength and sensibility with no evidence of premature growth plate closure or avascular necrosis of the talus.

Ankle Injuries↗
PubMed1996

Fractures of the hand.

In managing any fractures of the hand, the basic principles of fracture management are the same whether treatment is closed or open. They are 1. Accurate reduction and stabilization of the fracture 2. Elevation and edema control 3. Mobilization of the unaffected joints 4. Early range of motion of the injured digit or digits when healing processes permit. Special situations and injuries require amendments to the basic principles. Open fractures require early and thorough wound debridement. Early fixation and serial wound debridement to assure a proper environment for bone or skin grafting are essential in caring for these severe injuries (Figs. 13-15). Numerous fixation techniques ranging from simple plaster splints, K-wires, external fixators, and small plates and screws are available for fracture care. Fractures of the hand are very common injuries that demand early recognition and treatment. The majority of fractures can be treated with closed methods. Recognition of those injuries that require operative treatment and prompt attention to detail and surgical technique will prevent many of the complications associated with these frequently encountered problems.

Fracture Fixation↗