Biomedical subjects

Joseph H Schwab

Publications and source records attributed to Joseph H Schwab.

4 recordsLinked to original sources

PubMed2006

Function correlates with deltoid preservation in patients having scapular replacement.

Advocates of scapular replacement suggest sparing the deltoid should be a prerequisite for use of a scapular prosthesis. We evaluated the importance of a functioning deltoid in scapular replacement for malignant tumors. We retrospectively reviewed 19 patients who received scapular prostheses after resection of a malignant tumor. The median followup was 18 months (range, 12-124 months). The axillary nerve was resected in eight patients and spared in 11 patients. The average International Society of Limb Salvage score was 25 of 30 points (range, 21-27 points). The average scores for patients with and without axillary nerve resection were 24 points (range, 21-25 points) and 26 points (range, 23-27 points), respectively. There was a difference between the two groups in hand positioning, overall function, and pain. However, there were no differences in emotional acceptance, lifting ability, or hand dexterity. We favor using a scapular prosthesis if there is a functioning deltoid; however resection of the deltoid should not be considered an absolute contraindication for scapular replacement.

Adolescent↗

PubMed2006

Patellar complications following distal femoral replacement after bone tumor resection.

BACKGROUND: Patellar complications following endoprosthetic reconstruction can occur as a result of anatomic, physiologic, and surgical reasons. Patellar impingement on tibial polyethylene is a complication of distal femoral replacement, and it is frequently related to inaccurate restoration of the joint line and to soft-tissue contracture. The purpose of our study was to determine the prevalence and type of patellar complications following distal femoral replacements after excisions of bone tumors. METHODS: The results of reconstruction with use of a rotating-hinge endoprosthesis following excision of a distal femoral tumor in forty-three patients were retrospectively reviewed. Patients were followed clinically and radiographically for a minimum of forty-eight months or until death. Pain status, functional scores, and the range of motion were determined from a prospectively maintained database. The ratio of the patellar tendon length to the height of the patellar tendon insertion, as described by Insall and Salvati, was calculated. In addition, we attempted to determine whether the position of the patella was associated with anterior knee pain or with the functional scores derived with use of the International Society of Limb Salvage (ISOLS) scoring system. RESULTS: Thirty-five patellar complications, including eleven cases of impingement, occurred in twenty-seven patients (63%). We found no difference, on the basis of our sample size, with regard to the presence of patellar pain, the range of motion, or the Insall-Salvati ratio between the patients with and those without impingement. The ratio of the patellar tendon length to the height of the patellar tendon insertion averaged 0.9 in the group with impingement and 1.4 in the group without impingement (p = 0.07). The ISOLS score averaged 21.2 points in the group with impingement compared with 24.2 points in the group without impingement (p = 0.01). Patella baja occurred in nine patients. The average ISOLS score (and standard deviation) was 20.1 +/- 4.4 points for the patients with patella baja compared with 24.8 +/- 3.9 points in the group with a normal patellar position (p = 0.004). Patellar fracture occurred in two patients, and osteonecrosis occurred in two patients. These patients were treated nonoperatively. CONCLUSIONS: Patellar complications are common after distal femoral resection and endoprosthetic reconstruction. Patellar impingement on the polyethylene tibial bearing surface is a more common and important complication of distal femoral replacement than has been reported to date. Patella baja is also a relatively common complication, which has a negative impact on knee function.

Adult↗

PubMed2005

Flexion instability without dislocation after posterior stabilized total knees.

UNLABELLED: Flexion instability after cruciate-retaining total knee arthroplasty has been well documented. We identified an analogous patient group with symptomatic flexion instability without dislocation after primary posterior stabilized total knee arthroplasty. We sought to determine the typical symptoms and exam findings that lead to the diagnosis, to assess the reliability of revision total knee arthroplasty as a treatment, and to assess the technical difficulties encountered during revision total knee arthroplasty. Between 1995 and 2001, 10 patients had revision of a well-fixed posterior stabilized total knee arthroplasty for isolated symptomatic flexion instability. The typical constellation of symptoms and physical findings included a sense of instability without giving way, recurrent knee effusions, multiple areas of soft tissue tenderness about the knee, and substantial anterior tibial translation at 90 degrees of flexion. The revision operation focused on balancing the flexion and extension gaps while taking care to fill the enlarged flexion gap. Revision total knee arthroplasty was reliable in alleviating pain (mean Knee Society Pain scores improved from 68 points preoperatively to 89 points postoperatively), improving stability (nine of 10 patients had < 5 mm anterior tibial translation postoperatively) and improving patient satisfaction (nine of 10 patients were satisfied). We had no particular technical difficulties with the revision total knee arthroplasty procedures and had reliably achieved well-balanced flexion and extension gaps. LEVEL OF EVIDENCE: Therapeutic study, Level IV-1 (case series). See the Guidelines for Authors for a complete description of levels of evidence.

Aged↗

PubMed2003

A technique for treating periprosthetic fractures of the femur associated with deep prosthetic infection.

In this report a case of periprosthetic fracture of the femur associated with deep prosthetic infection after a total hip arthroplasty is treated in a novel way that allows for stabilization of the fracture and the delivery of local antibiotics. The technique allows the surgeon to stabilize the fracture and deliver antibiotics locally with a cement-coated Enders nail. This technique is useful in this combination of difficult problems as it facilitates the goals of eradicating infection, alleviating pain and improving function.

Aged↗