Arthroscopic Treatment of a Low-Velocity Gunshot Injury to a Primary Total Hip Arthroplasty: A Case Report

CASE

An immunosuppressed 51-year-old man sustained a ballistic injury about the site of a primary total hip arthroplasty, which had been performed for osteonecrosis of the femoral head 2 years earlier. He was treated with arthroscopic debridement and irrigation, inspection of the implants, and removal of foreign bodies.

CONCLUSION

Ballistic injury to a hip arthroplasty site with retained foreign bodies is an unusual injury. Hip arthroscopy may represent a minimally invasive treatment option for implant inspection, joint debridement, and removal of intra-articular fragments while minimizing the risk of soft-tissue complications.

Effects of hip joint transverse plane range of motion with a modeled effusion and capsular tear: A cadaveric study

BACKGROUND

Multiple factors contribute to range of motion of the hip joint in the transverse plane: bony anatomy, hip capsule, corresponding ligaments, articular labrum, ligamentum teres, and negative intra-articular pressure. We hypothesized that violation of the negative pressure of the hip and simulation of an effusion would increase range of motion in the transverse plane in a cadaver model.

METHODS

Ten hip specimens were obtained and dissected with the femur and iliac wing mounted in a custom joint-testing rig in neutral position. Specimens were tested at 0 and at 90° of flexion with 1.5Nm internal and external rotational torque. Three conditions were assessed: (1) intact specimen, (2) an effusion modeled by a 10ml saline infusion, and (3) a capsular tear.

FINDINGS

The modeled effusion decreased rotational range of motion limits in both 0 and 90° of flexion, with a greater effect on the specimens at 0° flexion in external rotation with 4.1° less external rotation (p=0.009). A modeled capsular tear increased rotational motion limits in 0° of flexion in both internal and external rotation and in 90° flexion in internal rotation only (p<0.025).

INTERPRETATION

An effusion may decrease the rotation of the hip, and a capsular tear may increase its rotation. This should be considered in hips with traumatic capsular tears or arthroscopic portals.

Knee arthrodesis using an intramedullary nail

Fifteen knee arthrodeses using an intramedullary nail were performed in 15 patients. Indications included 11 failed total knee arthroplasties (10 of 11 septic). A retrospective review revealed 100% fusion rate. Complications included 4 cases of painful hardware, 1 trochanteric bursitis, and 1 deep infection. Ten patients were available for assessment at 7 years follow-up. Average leg length discrepancy was 3.7 cm. Anatomic axis averaged 1.3 degrees valgus. Flexion angle averaged 3.5 degrees . Compared with age-matched controls, our patients fared significantly worse in physical functioning, physical role, bodily pain, vitality, and social functioning. Arthrodesis of the knee with an intramedullary nail provides a reliable means of fusion with reasonable alignment. These patients have high rates of pain and diminished functional status.