A Treatment Pathway Variation for Chronic Prosthesis-Associated Infections.

Periprosthetic joint infections (PJIs) are relatively rare but are on the rise because of the increasing total number of implantations performed. Treatment of PJI remains individualized and involves both surgical and medical treatment, with variations depending on the time of implantation, the duration and severity of the infection, tissue damage, and the underlying microorganism. In this case series study, we investigated clinical and functional outcomes of a variation of the Liestal algorithm in patients with PJI following total hip arthroplasty. METHODS: This study included 32 patients (33 cases) who were treated for chronic PJI with 2-stage exchange using a cement spacer during the period of 2003 to 2014. In contrast to other treatment pathways, antibiotic therapy was targeted to the causative microorganism as early as possible despite the presence of a cement spacer. Second-look surgery was performed 4 days after removal of the primary implant and a 4-week antibiotic-free window was interposed before definitive reimplantation. Thereafter, antibiotic treatment continued for approximately 6 weeks. All patients were followed for a minimum of 2 years. Parameters investigated were the duration of infection-free survival, functional outcome, and epidemiological data. RESULTS: At 2 years of follow-up and at the most recent follow-up (on average, 7 years after reimplantation), 100% of the patients were free of signs of infection, and the mean Harris hip score (HHS) was 89 at the latest follow-up. CONCLUSIONS: A meticulously performed 2-stage exchange for PJI with early targeted antibiotic treatment, second-look surgery, an antibiotic-free window before reimplantation, and antibiotic treatment post-reimplantation of medium duration is associated with excellent infection-related and good functional outcome after ≥2 years of follow-up even in cases of chronic PJI. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

No regeneration of the human acetabular labrum after excision to bone.

BACKGROUND: Treatment options for a symptomatic, torn, irreparable, or completely ossified acetabular labrum are limited to either excision and/or reconstruction with grafts. In a previous animal model, regeneration of the acetabular labrum after excision to the bony rim has been shown. In humans, less is known about the potential of regeneration of the labrum. Recent studies seem to confirm labral regrowth, but it is still unclear if wide excision might be a surgical option in cases where repair is not possible. QUESTIONS/PURPOSES: The purposes of this study were (1) to determine the extent of acetabular labrum regeneration after excision to the bony rim; and (2) to determine whether this procedure results in higher hip scores. METHODS: We reviewed all patients treated with surgical dislocation for symptomatic femoroacetabular impingement by a single surgeon at one institution between 2003 and 2008, of whom 14 underwent wide labral excision (of at least 60°) down to bone; we used this approach when there was an absence of reparable tissue. Of these 14, nine were available for voluntary reexamination. The mean age at surgery was 38 ± 9 SD years and the mean followup was 4 ± 1 SD years. All patients consented to a physical examination and an MRI arthrogram, which was evaluated for evidence of new tissue formation by four observers. A modified Harris hip score and the UCLA were recorded. RESULTS: Regrowth of a structure equivalent to normal labrum was not observed on the MRI arthrograms. Six of nine hips had segmental defects, bone formation was found in five, and the capsule was confluent with the new tissue in six. The mean Harris hip score at latest followup was 83 ± 14, and the mean UCLA score was 6 ± 2. CONCLUSIONS: Resection of a nonreparable acetabular labrum down to a bleeding bony surface does not stimulate regrowth of tissue that appears to be capable of normal function by MR arthrography, and patients who underwent this procedure had lower hip scores at midterm than previously reported from the same institution for patients undergoing labral repair or sparse débridement. Based on these results, we believe that future studies should evaluate alternatives to reconstructing the labrum, perhaps using ligamentum teres, because resection seems neither to result in regrowth nor the restoration of consistently high hip scores.

Sports and Activity Levels After Open Surgical Treatment of Femoroacetabular Impingement.

BACKGROUND: Several studies indicate that professional athletes can successfully return to competition after surgical treatment of femoroacetabular impingement (FAI). However, little is known about sports and activity levels after FAI surgery in the general patient population. HYPOTHESIS/PURPOSE: The purpose was to determine the sports behavior, satisfaction with sports ability, and activity levels in a consecutive cohort of patients with FAI who were treated by surgical hip dislocation. The hypothesis was that the majority of patients (>75%) would be active in sports at follow-up. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: This retrospective study included 153 patients (mean age, 30.0 years; 40.5% female) with 192 hips treated. Sports behavior and satisfaction were determined at a mean follow-up of 59.4 months with the use of a questionnaire. Activity levels at follow-up were assessed by the Hip Sports Activity Scale (HSAS) and the University of California, Los Angeles (UCLA) activity scale. RESULTS: Of 126 patients who were regularly active in sports before surgery, 107 (85%) were so at follow-up. Nineteen patients (12.4%) stopped participating in regular sports, and 8 (5.2%) commenced with sports after the operation. The most popular activities before surgery were skiing (22%), cycling (22%), jogging (20%), and soccer (13%). At follow-up, most patients were engaged in cycling (23%), fitness/weight training (20%), skiing (18%), and jogging (11%). Of all patients, 75% were satisfied with their sports ability, and 25% were not. Moreover, 60.3% stated that their sports ability had improved after surgery, 20.5% declared no change, and 19.2% were subjectively deteriorated. The mean pain level during sports was rated to be 2.1 according to the visual analog scale. The mean HSAS score was 3.5 (range, 0-8), and the mean UCLA score was 7.7 (range, 3-10); male patients reported significantly higher scores than did female patients on the HSAS (4.1 vs 2.7, respectively) and UCLA scale (8.2 vs 7.0, respectively). CONCLUSION: The vast majority of patients with FAI who are treated by surgical hip dislocation return to sports activities, and most patients are satisfied with their sports ability at midterm follow-up. Activity levels are significantly higher in male patients, but this does not yield higher satisfaction rates.

Extracortical plate fixation with new plate inserts and cerclage wires for the treatment of periprosthetic hip fractures.

PURPOSE: Fixation of periprosthetic hip fractures with intracortical anchorage might not be feasible in cases with bulky implants and/or poor bone stock. METHODS: Rotational stability of new plate inserts with extracortical anchorage for cerclage fixation was measured and compared to the stability found using a standard technique in a biomechanical setup using a torsion testing machine. In a synthetic PUR bone model, transverse fractures were fixed distally using screws and proximally by wire cerclages attached to the plates using "new" (extracortical anchorage) or "standard" (intracortical anchorage) plate inserts. Time to fracture consolidation and complications were assessed in a consecutive series of 18 patients (18 female; mean age 81 years, range 55-92) with periprosthetic hip fractures (ten type B1, eight type C-Vancouver) treated with the new device between July 2003 and July 2010. RESULTS: The "new" device showed a higher rotational stability than the "standard" technique (p < 0.001). Fractures showed radiographic consolidation after 14 ± 5 weeks (mean ± SD) postoperatively in patients. Revision surgery was necessary in four patients, unrelated to the new technique. CONCLUSION: In periprosthetic hip fractures in which fixation with intracortical anchorage using conventional means might be difficult due to bulky revision stems and/or poor bone stock, the new device may be an addition to the range of existing implants.

Midterm results of surgical hip dislocation for the treatment of femoroacetabular impingement.

BACKGROUND: Surgical treatment of femoroacetabular impingement (FAI) includes both open and arthroscopic procedures. Encouraging results have been reported for the majority of patients after surgical hip dislocation; however, most of these reports were short term and included only small cohorts. PURPOSE: To determine the results of surgical hip dislocation in a large cohort of FAI patients at a midterm follow-up. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A retrospective study including 185 consecutive patients (mean age, 30 years; 40% female) with 233 hips treated was conducted. We determined clinical outcomes in terms of range of motion and analyzed radiographs for several criteria including the alpha angle preoperatively and at 1 year postoperatively. At latest follow-up, on average 61 months postoperatively, patient satisfaction, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Hip Outcome Score, SF-12, and University of California, Los Angeles (UCLA) activity scale scores were determined. All revisions and conversions to total hip arthroplasty (THA) were recorded. RESULTS: Both hip flexion and internal rotation improved from preoperatively to postoperatively. Alpha angles decreased from 65.1° ± 14.2° to 42.4° ± 4.9°. At 5 years, 82% of the patients were satisfied or very satisfied with the results of surgery, and 81% would undergo the same surgery again. There were 83% who rated their overall hip function as normal or nearly normal. Mean scores for the WOMAC pain, stiffness, and function subscales were 10.3 ± 15.8, 15.9 ± 17.4, and 9.6 ± 13.0 points; for Hip Outcome Score activities of daily living and sport subscales were 89.0 ± 13.1 and 75.6 ± 23.0 points; and for the SF-12 Physical Component Scale and Mental Component Scale were 47.4 ± 6.3 and 52.3 ± 7.4 points, respectively. The mean UCLA activity level was 7.7 ± 1.9. Conversion to THA was performed in 7 hips (3%). Seven hips (3%) underwent other major revisions, and 11 (4.7%) underwent minor revisions. Female patients had a significantly increased risk for conversion to THA (odds ratio, 13.3; 95% confidence interval [CI], 1.3-92.6) and major revision (odds ratio, 19.2; 95% CI, 2.4-152.9). The mean body mass index was significantly lower in those patients who underwent conversion to THA. The need for microfracture because of residual full-thickness cartilage defects after rim trimming was a significant (P = .04) predictor of subjective dissatisfaction. CONCLUSION: This study demonstrates that surgical hip dislocation is a successful procedure for the treatment of FAI. A majority of patients were satisfied with the results of surgery at a midterm follow-up. Older and slim female patients were at an increased risk for a less successful outcome in terms of conversion to THA and revision surgery.

Surgical hip dislocation for the treatment of femoroacetabular impingement in high-level athletes.

BACKGROUND: Midterm outcome studies show that symptomatic femoroacetabular impingement (FAI) can be successfully treated by addressing the underlying pathomorphology with open or arthroscopic surgery. Although athletes may be vulnerable to hip injury from impingement, limited information is available regarding the results of open surgery in this group. HYPOTHESIS: High-level athletes with FAI can resume their sports after surgical hip dislocation and continue professional careers for a significant period. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Twenty-two professional male athletes (19.7 ± 2.2 years) were evaluated by postal survey at a mean of 45.1 months (range, 12 to 79) after treatment by surgical hip dislocation (30 hips, cam- or mixed-type FAI; mean α angle, 69.3°; 14 ice hockey players). Evaluation included types and level of sports, subjective ratings, and CLINICAL OUTCOMES: Hip Outcome Score, SF-12, UCLA (University of California, Los Angeles) activity scale, Hip Sports Activity Scale, visual analog scale for pain. The primary outcome variable was return to professional sports; the clinical result was the secondary outcome variable. RESULTS: At follow-up, 21 of 22 patients (96%) were still competing professionally: 19 at their previous level and 2 in minor leagues. Eighteen (82%) were satisfied with their hip surgery and 19 (86%) with their sports ability. Mean activity levels were 9.8 per the UCLA scale and 7.6 per the Hip Sports Activity Scale. Mean scores of the Hip Outcome Score-Activities of Daily Living and Sport subscales were 94.5 and 89.1. Mean scores of the SF-12 physical and mental component summaries were 51.1 and 54.3. Pain levels during sports were 1.8 per the visual analog scale. CONCLUSION: Surgical hip dislocation for the treatment of FAI allows athletes to resume sports and continue professional careers at the same level for several years. Clinical outcomes in terms of subjective ratings and scores were favorable.

Late repair of abductor avulsion after the transgluteal approach for hip arthroplasty.

The abductor release sometimes does not heal after a transgluteal approach for hip arthroplasty. Factors influencing the success of subsequent repair are unclear. We used magnetic resonance imaging (MRI) to compare the condition of the gluteus medius with clinical outcome after late repair of abductor dehiscence in 12 total hip patients. Evaluation included a pain rating, gait evaluation, Trendelenburg test, strength grading, and Harris Hip Score. Most had both prerepair and postrepair MRI studies to assess the repair and to grade abductor muscle fatty degeneration. Two repairs without MRI were explored surgically. Although average pain, limp, and strength scores improved significantly, rerupture occurred in 4 subjects and fatty degeneration in the gluteus medius did not improve, even with intact repair. Nine patients were satisfied; 7 of these had an intact repair. Magnetic resonance imaging and operative observations suggest that chronic degeneration in the abductor mechanism is the major impediment to successful repair.

Stepped osteotomy of the trochanter for stable, anatomic refixation.

Refixation of a trochanteric osteotomy carries a high complication rate. To enhance stability and facilitate anatomic reduction of the trochanteric fragment, we have introduced a stepped osteotomy. Between April 2006 and June 2007, we performed surgical hip dislocations using the modified trochanteric osteotomy combined with a relatively aggressive rehabilitation program. Full weightbearing was allowed at a mean of 42 days (range, 33-54 days). The minimum followup was 8 months (median, 13 months; range, 8-24 months). Postoperative radiographs were assessed prospectively for consolidation or the appearance of malreduction/nonunion/malunion of the osteotomy and heterotopic ossification. In 110 of 113 hips, the trochanteric osteotomy healed in the anatomic position. Two patients had a trochanteric delayed union with loss of anatomic position, and one additional patient underwent revision surgery for a pseudarthrosis and cranial migration of the trochanteric fragment. All three complications related to healing occurred in the first 60 patients when the step height was 3 to 4 mm. After increasing the step heights to 6 mm, we observed no healing complications. Despite more aggressive postoperative mobilization, the incidence of malunion or nonunion related to the new stepped osteotomy is low and approaches zero for steps of 6 mm. It is now our technique of choice.

Femoroacetabular impingement in professional ice hockey players: a case series of 5 athletes after open surgical decompression of the hip.

BACKGROUND: Femoroacetabular impingement of the hip joint has been identified as a major cause for hip pain in athletes. Surgical open decompression of the hip has historically been proposed as the first treatment of choice. Functional outcomes in athletes after this procedure are unknown. PURPOSE: To describe the functional and sport-related outcome 2 years after open surgical hip decompression in a group of young professional ice hockey players suffering from cam femoroacetabular impingement. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Five young professional ice hockey players (mean age, 21.4 y at follow-up) who suffered from cam femoroacetabular impingement were treated with open surgical decompression of the hip. The operation was performed by the same surgeon, and all athletes followed the same rehabilitation guidelines. Mean follow-up time was 2.7 years. Outcome measures were recorded as time to regain symmetrical hip rotation, regain preoperative core/hip muscle strength, return to team practice, and play at competitive level. RESULTS: Hip rotation range of motion was regained by a mean 10.3 weeks. Core and hip strength values reached preoperative levels by a mean 7.8 months. Return to unrestricted team practice with the ice hockey team was achieved by a mean 6.7 months, and athletes were able to play their first competitive game after a mean 9.6 months. Three athletes were able to perform again at the highest level and in international competitions. Two athletes had to return to minor league ice hockey. CONCLUSION: Return to high-level ice hockey after open surgical decompression of the hip was possible in this series of 5 consecutive cases.

Correlation between internal rotation and bony anatomy in the hip.

Femoroacetabular impingement has been implicated as a risk factor for degenerative arthritis in young people with normally concentric hips. On presentation, patients with impingement have groin pain, limited internal rotation in 90 degrees flexion, and focal articular lesions. We hypothesized that the amount of internal rotation is dictated primarily by the underlying bony anatomy and not secondary to contractures. We compared 23 consecutive patients (32 hips) with 40 asymptomatic control subjects using positional magnetic resonance imaging, physical examination, and a questionnaire regarding symptoms and their commencement. There was a strong correlation between internal rotation in 90 degrees flexion and the measurable free space between the relevant bony contours on magnetic resonance imaging (r = 0.97) in the patient group and the control subjects. The range of internal rotation is closely related to skeletal anatomy, and internal rotation can be used as a noninvasive tool to predict the risk of impingement.

Abductor tendons and muscles assessed at MR imaging after total hip arthroplasty in asymptomatic and symptomatic patients.

PURPOSE: To prospectively evaluate magnetic resonance (MR) imaging findings of abductor tendons and muscles in asymptomatic and symptomatic patients after lateral transgluteal total hip arthroplasty (THA). MATERIALS AND METHODS: The institutional review board approved the study, and all patients provided informed consent. Two musculoskeletal radiologists blinded to clinical information analyzed triplanar MR images of the greater trochanter obtained in 25 patients without and 39 patients with trochanteric pain and abductor weakness after THA. Tendon defects, diameter, signal intensity, and ossification; fatty atrophy; and bursal fluid collections were assessed. In 14 symptomatic patients, MR imaging and surgical findings were correlated. Differences in the frequencies of findings between the two groups were tested for significance by using chi2 analysis. RESULTS: Tendon defects were uncommon in asymptomatic patients and significantly more frequent in symptomatic patients: Two asymptomatic versus 22 symptomatic patients had gluteus minimus defects (P < .001); four asymptomatic versus 24 symptomatic patients, lateral gluteus medius defects (P < .001); and no asymptomatic versus seven symptomatic patients, posterior gluteus medius defects (P = .025). In both patient groups, tendon signal intensity changes were frequent, with the exception of those in the posterior gluteus medius tendon, which demonstrated these changes more frequently in symptomatic patients (in 23 vs five asymptomatic patients, P = .002). Tendon diameter changes were frequent in both groups but significantly (P = .001 to P = .009) more frequent in symptomatic patients (all tendon parts). Fatty atrophy was evident in the anterior two-thirds of the gluteus minimus muscle in both groups, without significant differences. In the posterosuperior third of the gluteus minimus muscle, however, differences in fatty atrophy between the two groups were significant (P = .026). Fatty atrophy of the gluteus medius muscle was present in symptomatic patients only, with significant differences among all muscle parts. Bursal fluid collections were more frequent in symptomatic patients (n = 24) than in asymptomatic patients (n = 8, P = .021). The MR imaging-based diagnosis was confirmed in all 14 patients who underwent revision surgery. CONCLUSION: Abductor tendon defects and fatty atrophy of the gluteus medius muscle and the posterior part of the gluteus minimus muscle are uncommon in asymptomatic patients after THA.

FDG PET for differentiation of infection and aseptic loosening in total hip replacements: comparison with conventional radiography and three-phase bone scintigraphy.

PURPOSE: To compare the diagnostic efficacy of fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) with that of conventional radiography and three-phase bone scintigraphy in patients suspected of having infection in their total hip replacements. MATERIALS AND METHODS: Thirty-five patients with painful total hip replacements and possible septic prosthetic loosening were examined with FDG PET, conventional radiography, and three-phase bone scintigraphy. PET, radiographic, and scintigraphic images were each evaluated by two independent observers in a blinded fashion. For 32 of 35 patients, serial conventional radiographs were available. Results of microbiologic examinations of surgical specimens represented the standard of reference in 26 patients, and results of joint aspiration plus clinical follow-up of at least 6 months represented the standard of reference in the remaining nine patients. Sensitivity, specificity, accuracy, and interobserver variability (kappa) values were calculated. The imaging modalities were compared in terms of diagnostic confidence by using the sign test. RESULTS: Nine patients had septic and 21 patients had aseptic loosening. In five patients, neither loosening nor infection was confirmed. For diagnosing infection with FDG PET, conventional radiography, and bone scintigraphy, respectively, sensitivity values for reader 1 and reader 2 were 33% and 22%, 89% and 78%, and 56% and 44%, while specificity values were 81% and 85%, 50% and 65%, and 88% and 92% and accuracy values were 69% for both readers, 60% and 69%, and 80% for both readers. PET was significantly more specific (P =.035) but less sensitive (P =.016) than conventional radiography for the diagnosis of infection. CONCLUSION: In a study population of patients suspected of having infected total hip replacements, FDG PET performed similarly to three-phase bone scintigraphy. FDG PET was more specific but less sensitive than conventional radiography for the diagnosis of infection.

Acetabular blood flow during Bernese periacetabular osteotomy: an intraoperative study using laser Doppler flowmetry.

BACKGROUND: The blood flow to the acetabular fragment is of some concern in juxtaarticular pelvic osteotomies used for the treatment of hip dysplasia. No direct measurements have determined the effect of the Bernese periacetabular osteotomy (PAO) on acetabular perfusion. METHODS: Acetabular perfusion was measured by means of laser Doppler flowmetry in 10 patients undergoing a PAO for symptomatic acetabular dysplasia. During the surgical procedure, the intraosseous high energy laser Doppler reliably depicts dynamic changes of small vessel blood flow. Measurements were performed after defined surgical steps to obtain sequential information on the blood perfusion of the acetabular fragment. RESULTS: After complete separation of the acetabular fragment, nine out of 10 patients had pulsatile signals, but the blood flow (BF) significantly decreased by 77%. Corrective positioning of the fragment induced no further drop of the BF signal but a loss of pulsatility in six patients. After a recovery period of about 30 min following preliminary fixation of the fragment, reestablishment of the pulsatile signal and an increase of the BF signal was seen. At termination of the surgical procedure, five out of eight patients, who could be followed throughout the whole procedure, showed a clear pulsatile signal in the supraacetabular area. Bleeding of the supraacetabular cancellous surface could be observed in all acetabula. CONCLUSION: Despite careful preservation of soft tissues during the surgical procedure, a significant reduction of the blood flow in the supraacetabular region has been observed. Nevertheless, a pulsatile signal in more than 60% of the fragments after fragment correction and an increasing signal during the recovery period showed ongoing blood perfusion indicating reversible changes in the measured supraacetabular area. All osteotomies healed within eight weeks without showing signs of necrosis during a minimum follow up of 1 year.

Cartilage lesions in the hip: diagnostic effectiveness of MR arthrography.

PURPOSE: To evaluate the diagnostic performance of magnetic resonance (MR) arthrography in the detection of articular cartilage lesions in patients suspected of having femoroacetabular impingement and/or labral abnormalities. MATERIALS AND METHODS: Forty-two MR arthrograms obtained in 40 patients with a clinical diagnosis of femoroacetabular impingement and/or labral defect were retrospectively analyzed. Two readers independently interpreted the images for cartilage lesion location, depiction, and characteristics. Within 6 months after MR arthrography, each patient underwent open hip surgery, during which the entire cartilage of the hip joint was inspected. Sensitivity, specificity, accuracy, and positive and negative predictive values were calculated. kappa values were calculated to quantify the level of interobserver agreement. RESULTS: At surgery, most (37 [88%] of 42) cartilage defects were identified in the anterosuperior part of the acetabulum. In 23 (55%), 12 (29%), 10 (24%), and 10 (24%) hips, lesions were found in the posterosuperior acetabulum, anteroinferior acetabulum, posteroinferior acetabulum, and femoral head, respectively. The sensitivities and specificities of MR arthrographic detection of cartilage damage in all regions combined were 79% (73 of 92 regions) and 77% (91 of 118 regions), respectively, for reader 1 and 50% (46 of 92 regions) and 84% (99 of 118 regions), respectively, for reader 2. At interobserver comparison, agreement was fair (kappa = 0.31) for detection of cartilage lesions in the femoral head and poor (kappa