INTRODUCTION

Wedge femoral stems used in total hip arthroplasty (THA) have evolved with modifications including shorter lengths, reduced distal geometries, and modular necks. Unlike fit and fill stems which contact most of the metaphysis, tapered wedge femoral stems are designed to achieve proximal medial/lateral fixation. These single taper, wedge stems have demonstrated positive clinical outcomes. The tapered wedge stem evaluated in this study has further reduced distal geometry to provide a wedge-fit within the metaphysis of the proximal femoral canal for all femur types (Dorr A, B, C). The objective of this study was to evaluate the early clinical outcomes, including femoral stem subsidence, of a tapered wedge femoral stem.

Purpose: In this study we comprehensively evaluate a cohort of profoundly affected adults with Cerebral Palsy. We document hip disability and pain and statistically evaluate the effect of demographic, physical examination (PE) and radiographic parameters on pain and function of the hip.

Methods: We evaluated 77 institutionalized patients with cerebral palsy. Medical history, level of function, pain, and analgesic requirements were obtained from record review and through caregiver interview. Range of motion (ROM), degree of spasticity, decubitus ulcers were documented as well as changes in vital signs and the FLACC pain scale during PE. Radiographs of the pelvis and spine were blindly evaluated without knowledge of the above data. Statistical analysis was performed in order to identify correlations between subjective and objective findings from the history and PE with radiographic parameters in these patients.

Results: Participants included 38 men and 39 women with a mean age of 40 years (range, 22-81), 94 % had severe spastic quadriplegia. Fifteen percent of hips were dislocated and radiographic evidence of arthritis was noted in 23 %. Eighteen percent of hips were definitely painful and 45 % were definitely not painful. Higher rates of dislocation and arthritis were noted in older patients (p< .05). Increased hip pain and perineal care problems were noted in patients with decreased hip abduction (p=.01), windswept hip deformities (p=.02) or flexion contractures (p=.07). Increased spasticity was associated with higher rates of arthrosis, dislocation, pain and decubiti. Hip dislocation and subluxation sig-nificantly correlated with osteoarthritis (p< .0001) but not hip pain. Patients with lower CE (< 20°) or higher Sharps (> 40°) angles were more likely to have a history of hip pain (p=.02). No radiographic parameter correlated with increased analgesic use, or change in FLACC score or vital signs during PE of the hip.

Conclusions: From these adult cerebral palsy patients we document pain and poor perineal care in patients with diminished hip range of motion and windswept hip posture. Hip dislocation and arthritis was noted in 15 and 23 % of hips, with definite pain noted in 18 %. Ace-tabular dysplasia was statistically associated with hip pain; however, in this study we could not correlate hip displacement or arthritis with a history of hip pain or diminished function. Because the incidence of hip pain is low and does not correlate with dislocation or arthritis, we suggest that surgical treatment of hips in severely affected immature patients with cerebral palsy be based on presence of pain or contractures and not on radiographic signs of hip displacement.