To characterize the quality of flap tissues and the resident cells in order to provide a scientific rationale for reattaching flap tissues during surgery.

11 acetabular chondral flaps and 3 non-delaminated cartilage samples were resected during open hip surgeries and the anatomical orientation was marked. The viability was measured in 7 flaps with Live Dead staining and the distribution of the extracellular matrix components was investigated in 7 oriented flaps by histology. The chondrogenic potential of the residing cells (P2) was investigated via pellets assays (5 flaps). Their capacity to outgrow from flap particles was tested upon encapsulation in 4mm-diameter fibrin glue discs (6 flaps).

The viability in flaps was 49.4 ± 6.5 % compared to 70.6 ± 8.2 % in non-delaminated cartilage, (not significant). Histology showed a progression of fibrillation from the delaminated side towards the site of attachment. This degraded state correlated with the capacity of the cells to outgrow, with 60.6 ± 33 % of the gel area covered by migrating cells after 4 weeks in culture. However, the cells in flaps showed a decreased chondrogenic potential than chondrocytes from non-delaminated cartilage.

Our findings indicate that flaps contain viable cells that can outgrow from the tissue due to the degraded state of the matrix. The poor chondrogenic property of the cells suggests they are unlikely to produce enough matrix to provide a solid attachment of the delaminated tissue upon migration.

The classical longitudinal incision used for the direct anterior approach (DAA) does not follow the relaxation tension lines of the skin and can lead to impaired wound healing and poor scar cosmesis. The purpose of this study was to determine patient functional and radiographic outcomes of a modified skin crease “bikini” incision used for the DAA in THR.

964 patients (51% female; 59% longitudinal, 41% bikini) completed 2 to 4 years after surgery a follow-up questionnaire including the Oxford Hip Score (OHS), the University of North Carolina 4P scar scale (UNC4P), and two items for assessing aesthetic appearance and symptoms of numbness. Implant position, rates of radiographic heterotopic ossification and required revision were assessed.

UNC4P total (p<0.001) and OHS (p=0.013) scores were better in the bikini compared the longitudinal group. The proportion of aesthetically very satisfied patients was higher (p<0.001) in the bikini group. The proportion of patients reporting numbness in the scar was higher (p<0.001) in the longitudinal (14.5% versus 7.5%, respectively). Radiographic cup abduction angles, stem position and ectopic ossification rates did not differ between the groups. No differences in the revision rates of both groups being 2.1% in the longitudinal and 1.5% in the Bikini group. Although differences were not huge, Bikini incision resulted in better patient-related outcomes and satisfaction related to the scar. Our study showed that a short oblique “bikini” skin crease incision for the DAA can be performed safely without compromising implant positioning or increasing symptoms suggesting lateral femoral cutaneous nerve dysesthesia. As it is less extensile it should be used after having gained significant experience with the classic longitudinal incision.

Background

Second-generation high-carbon CoCrMo-alloy metal-on-metal total hip arthroplasty (THA) was introduced in the late 1980s following reports of early loosening, impingement, pronounced wear, and hypersensitivity in the first-generation metal-on-metal articulations. There has been inconsistent data that specifically addresses the clinical performance and longevity of second-generation metal-on-metal THA. The purpose of this study was to evaluate the survival of second-generation metal-on-metal primary THA and to assess the influence of demographic factors on implant survival in a large patient cohort.

Evidence has emerged that femoroacetabular impingement (FAI) may instigate early osteoarthritis of the hip and that symptomatic patients can be successfully treated by addressing the underlying pathomorphology. There is also an increasing body of evidence to support FAI as one major cause of hip and groin pain, decreased mobility and reduced performance in athletes. This study therefore aimed to investigate if professional athletes with FAI can resume to their sports after a surgical dislocation of the hip and continue their professional career up to a mid-term follow-up. We identified fifteen professional athletes (21 hips, all cam-type or mixed-type FAI, mean alpha-angles of 68°) who underwent a surgical hip dislocation for FAI treatment. Surgery was performed by the senior author in all cases. The patients were evaluated by postal survey at a mean of 47 months (range, 9–79) postoperatively. The evaluation inquired about the type and level of sports, subjective ratings, and clinical outcomes (Hip Outcome Score [HOS], SF-12, UCLA activity scale, FAI sports scale [FSS], VAS pain). At follow-up, 14 of the 15 patients (93%) were still professionally sports active. Twelve athletes maintained their levels and two were active in minor leagues. Eleven patients (75%) were satisfied with their hip surgery and their sports ability. Mean activity levels were 7.5 according to the self-developed FSS and 9.7 according to the UCLA scale, respectively. Mean scores of the HOS ADL and Sport subscales were 92.6 and 85.2, respectively. Mean scores of the SF-12 PCS and MCS were 50.7 and 56.1, respectively. Pain levels during sports were rated to be 2.0 according to the VAS. In conclusion, this study highlighted that professional athletes suffering from FAI can successfully return to professional sports after a surgical dislocation of the hip. All athletes except one (93%) could continue their professional career up to the follow-up four years after surgery. Clinical outcomes in terms of subjective ratings and scores were encouraging, nevertheless, longer-term follow-up has to show if results deteriorate with time considering the exhaustive joint use related to a professional sports career.

Syndactyly is hereditary observed in animals and humans. While the syndactyly between fingers is normally surgically released, syndactyly between toes rarely requires treatment. Considering this observation, a surgical syndactylization has been already postulated more than 50 years ago as a salvage procedure in severe recurrent toe deformities to avoid amputation. Since then, only few sporadic case reports have been published, mainly focusing on techniques rather than on outcomes. This study describes our surgical technique and the clinical results in 15 patients (13 females, mean age 58.3 years) at a mean of 32 months after surgical syndactylization for the treatment of 18 severe toe deformities (10 digitus superductus, 5 digitus varus, 3 hammer toes, 2 floppy toes, 2 floating toes). All patients suffered from recurrent deformities after failed previous surgery. We noted all complications and revisions. Clinical outcomes were assessed using subjective ratings and the American Orthopaedic Foot and Ankle Society (AOFAS) score for the lesser toes. There occurred no intra- or postoperative complications and no revision surgery was necessary. Eleven patients (73%) were very satisfied with the operative results, and four (27%) were satisfied. Preoperatively, only two patients (13%) were satisfied with the cosmetic appearance of their feet while all patients (100%) were very satisfied or satisfied at follow-up. Thirteen patients (87%) would undergo the same type of surgery again, and one patient (7%) would not. AOFAS scores significantly improved from 33.1 ± 18.4 points preoperatively to 84.0 ± 14.4 points at follow-up (p< 0.0001). The present results demonstrated that the surgical syndactylization between toes is a successful salvage procedure for the treatment of recurrent severe toe deformities. Subjective ratings regarding patient satisfaction and the cosmetic appearance were excellent and AOFAS scores significantly improved. Hence, the surgical syndactylization should be considered as an alternative treatment option instead of toe amputation.

Physical inactivity is a modifiable lifestyle-related risk factor considered one of the leading causes for the major noncommunicable chronic diseases and relates to approximately 250,000 deaths per year in the United States. While the benefits of physical activity (PA) are many and well-known, qualitative research defining the type and amount of PA in total joint arthroplasty (TJA) patients that improves health without disproportionally increasing wear and revision rates does unfortunately not exist in the literature. As the basis for future research, this systematic review therefore aimed to identify the different instruments used up to now to quantify PA in TJA patients and to determine how active these patients really are. Within the 26 studies included (n=2460 patients), motion sensors and recall questionnaires were most commonly used. The reported Results were mainly descriptive and research aims and goals varied widely between the studies. We were able to meta-analytically summarize the Results of those studies quantifying PA using pedometers and accelerometers. Patients took a weighted mean of 6,721 steps/day (95% CI: 5,744 to 7,698). Steps per day determined by accelerometers were 2.2 times more than steps assessed by pedometers. Meta-regression demonstrated that walking activity decreased by 90 steps/day (95% CI: −156 to −23) every year of patient age. These summarized Results clearly indicate that TJA patients are less active than recommended to achieve health-enhancing activity levels (currently > 10,000 steps/day), but they are more active than normally assumed in wear-simulations. Hence, such simulator Results have to be interpreted cautiously, taking into account that one million cycles correspond to less than one year in vivo. Future investigations have to evolve more standardization in the assessment and reporting of PA in TJA patients.

Concerns recently arose regarding hip resurfacing arthroplasty (HRA), mainly referring to the metal-on-metal articulation that results in increased metal ion concentrations and that may be associated with weird soft tissue reactions. Although a number of short-term reports highlighted excellent and encouraging outcomes after HRA, mid- to long-term follow-up studies are sparse in the current literature. This study aimed to determine the five-year results of HRA using the Durom^® prosthesis in the first consecutive 50 cases. We prospectively assessed clinical and radiographic data for all patients undergoing HRA with this implant. Follow-ups were scheduled at six weeks, one year, two years and five years after surgery. All complications, revisions and failures were noted. Harris Hip Scores (HHS) and the range of motion (ROM) were determined preoperatively and at each follow-up. Oxford Hip Scores (OHS) and University of California at Los Angeles (UCLA) activity levels were determined at the last control. Comparisons were performed using paired t-tests after testing for normal distribution. The cohort comprised 13 women and 36 men (50 hips) with a mean age of 53.3 ± 10.7 years and a mean BMI of 25.9 ± 3.7 kg/m2. After a mean follow-up of 60.5 ± 2.3 months five hips had to be revised, corresponding to a resvision rate of 10%. There occurred two femoral neck fractures (after two and eleven months) and one aseptic loosening of the femoral component (after 68 months). One implant was exchanged to a conventional stem-type design due to persistent hip pain (after eight months), and one hip underwent a femoral offset correction due to a symptomatic impingement between the neck and the cup (after 29 months). There occurred no intra- or other postoperative complications. Clinically, ROM significantly improved after surgery. Hip flexion increased from 91.1 ± 15.8° to 98.9 ± 6.5° (p=0.0007), internal rotation from 5.5 ± 6.9° to 11.1 ± 8.1° (p=0.0005), external rotation from 19.2 ± 12.5° to 28.8 ± 9.1° (p=0.0001), and abduction from 27.3 ± 10.5° to 40.2 ± 11.0° (p< 0.0001). The HHS significantly increased from 55.9 ± 12.3 points to 96.5 ± 8.5 points. The OHS averaged 14.3 ± 3.0 points, and UCLA activity levels averaged 7.7 ± 1.7. The present results demonstrate that despite satisfactory clinical outcomes in terms of patient scores and ROM, the high revision rate of 10% after a mid-term follow-up is disappointing.

During the last decade, outcome assessment in orthopaedic surgery has increasingly focused on patient self-report questionnaires. The Oxford Hip and Knee Scores (OHS and OKS) were developed for the self-assessment of pain and function in patients undergoing joint replacement surgery. These scores proved to be reliable, valid, and responsive to clinical change, however, no German version of these useful measures exists. We therefore cross-culturally adapted the OHS and OKS according to the recommended forward/backward translation protocol and assessed the following metric properties of the questionnaires in 105 (OHS) and 100 (OKS) consecutive patients undergoing total hip or knee replacement in our clinic: feasibility (percentage of fully completed questionnaires), reliability (intraclass correlation coefficients (ICC) and Bland and Altman’s limits of agreement), construct validity (correlation with the Western Ontario and McMaster Universities Index (WOMAC), Harris Hip Score (HHS), Knee Society Score (KSS), Activities of Daily Living Scale (ADLS), and Short Form (SF-)12), floor and ceiling effects, and internal consistency (Cronbach’s alpha, CA). We received 96.6% (OHS) and 91.9% (OKS) fully completed questionnaires. Reliability of both questionnaires was excellent (ICC > 0.90). Bland and Altman’s limits of agreement revealed no significant bias. Correlation coefficients with the other questionnaires ranged from −0.30 (SF-12 Mental Component Scale) to 0.82 (WOMAC) for the OHS, and from −0.22 (SF-12 Mental Component Scale) to −0.77 (ADLS) for the OKS. For both questionnaires, we observed no floor or ceiling effects. The internal consistency was good with a CA of 0.87 for the OHS and 0.83 for the OKS. In conclusion, the German versions of the OHS and OKS are reliable and valid questionnaires for the self-assessment of pain and function in German-speaking patients with hip or knee osteoarthritis. Considering the present results and the brevity of the measures, we recommend their use in the clinical routine.

The goal of this study was to develop and validate a short, evaluative self-report questionnaire for the clinical self-assessment of patients with hip osteoarthritis (OA). If used together with other self-report outcome tools (e.g. generic or physical activity measures), such a short joint-specific questionnaire could avoid an increased burden to the patients and decrease the risk of data loss. All items of the new score (Schulthess Hip Score, SHS) were generated solely on patient perceptions, for item removal we used the clinical severity-importance rating and inter-item correlation methods. The final score consisted of only five items. We then assessed the following metric properties of the SHS in 105 consecutive patients with symptomatic hip OA (mean age, 63.4 ± 11 years, 48 women) undergoing total hip arthroplasty (THA) in our clinic: proportion of evaluable questionnaires, reproducibility, internal consistency, concurrent validity, and responsiveness. 97% of the questionnaires were evaluable. Reproducibility of the SHS was excellent (intraclass correlation coefficient (ICC) 0.90; standard error of the measure (SEM) 6.4). Exploratory factor analysis indicated that all items loaded on only 1 factor which accounted for 69.4% of the total variance. Cronbach’s alpha was 0.88. Evidence of convergent validity was provided by moderate to high correlations with scores and subscales of the WOMAC (r = 0.58–0.78), Oxford Hip Score (r = 0.78), Harris Hip Score (r = 0.37), SF-12 physical component scale (r = 0.57), UCLA activity scale (r = 0.48), and Tegner score (r = 0.53). Evidence of divergent validity was provided by a lower correlation with the SF-12 mental component scale (r = 0.37). The SHS proved to be responsive with an effect size (ES) of 2.15 and a standard response mean (SRM) of 1.74 six months after THA. Taken together, the results of this study provide evidence to support the use of the five-item self-report SHS in patients with hip osteoarthritis. Considering the brevity of this score, it could be easily used together with other measures such as generic and physical activity assessment tools, without overburdening patients with an inordinate number of items and questions.

There is only a paucity of information on the outcome of resurfacing arthroplasty in patients suffering from hip osteoarthritis secondary to developmental dysplasia (DDH). When performing arthroplasty in dysplastic hips, the anatomic abnormalities offer reconstructive challenges, in particular in resurfacing. The present study was therefore conducted to address the following questions: Can hip resurfacing arthroplasty provide satisfactory clinical results in patients with DDH? Can the patients return to sports and recreational activities? Can the hip biomechanics be restored? And finally, can surface arthroplasty reestablish a normal, symmetric gait pattern? The study comprised 24 consecutive patients (32 hips) with a mean age of 44.2 years who underwent surface replacement due to hip osteoarthritis secondary to DDH. Surgery was performed by two senior surgeons using either the Durom implant or the Birmingham Hip Resurfacing prosthesis, dependent on the surgeon’s preference. At a mean follow-up of 43 months, all patients were evaluated cross-sectionally. We assessed clinical and radiographical data and investigated spatiotemporal gait parameters using an electronic mat. The Harris Hip Score improved from 54.7 +/−13.3 to 97.3 +/−5.2 (p< 0.001) and University of California at Los Angeles (UCLA) activity levels increased from 5.3 +/−2.0 to 8.6 +/−1.6 (p< 0.001), respectively. Hip flexion improved from 95.7° +/−16.5° to 106.7° +/−10.6° (p< 0.001). At a mean of 11.2 +/−4.8 weeks after surgery, all patients returned to sports activity. They participated in a mean of 6.0 +/−2.6 different disciplines, 2.8 +/−1.3 times and 4.1 +/−3.6 hours per week. The most common disciplines were cycling, swimming, exercise walking and downhill-skiing. Spatiotemporal parameters of gait demonstrated a symmetrical gait pattern without major differences to normative data. Both, the hip lever arm ratio and the femoral offset increased significantly (p< 0.001) from 0.48 +/−0.07 to 0.57 +/−0.08 and from 39.3 +/−8.2 mm to 45.6 +/−6.2 mm, respectively. Grade I heterotopic ossifications were seen in two hips, there were no Grade II or III ossifications. Two surface replacements failed, both failures could be attributed to surgical errors. The surface arthroplasty risk index was 3.2 +/−1.4 for the entire cohort and 4.5 for the revision cases. Femoral radiolucencies were detected in ten of the remaining 30 hips. The present study demonstrated that hip resurfacing achieved satisfactory clinical results in patients with hip osteoarthritis secondary to DDH. The failure rate of 6.3% did not reach our expectations, however, both failures could be attributed to surgical errors. Further follow-up is nevertheless of utmost importance to assess the significance of femoral stem radiolucencies in this young and active group of patients.

Introduction: Rotational alignment of the femoral component is widely believed to be crucial for the ultimate success of total knee arthroplasty (TKA). However there is a paucity of normative data on femoral component rotation in ‘perfect’ TKA.

Methods: Femoral component rotation in well-functioning TKA was assessed by means of axial radiography as described by Kanekasu et al. Well-functioning TKA were defined by three criteria at 5-year follow-up:

Knee Society objective and functional score of 190 or above

Thirty TKA of 29 patients (9 male, 20 female) with a median age of 70 years (range, 31–87) at time of surgery fulfilled the study criteria. All TKA were implanted at a single high-volume joint replacement center in 2002. In all cases both the condylar twist angle (CTA) using the clinical epicondylar axis (CEA) and the posterior condylar angle (PCA) using the surgical epicondylar axis (SEA) were used to assess rotational alignment of the femoral component.

Results: Overall, the mean CTA was 3.6+−3.5° of internal rotation (IR) (range, 4.1° of external rotation (ER) to 8.6° of IR) for the femoral component. For females, the CTA had a mean value of 4 +/−3.7° of IR (range, 7.6° of IR to 4.1° of ER) compared to 2.3 +/−3° of IR (range, 5.3° of IR to 2.5° of ER) in males. Overall, the mean PCA was 1.5 +/−3.5° of ER (range, 8.4° of ER to 5.1° of IR). In females, the mean PCA was 1 +/−3.9° ER (range, 2.3° of IR to 5.8° of ER) compared to 2.8 +/−2° ER (range, 0.4° of ER to 5.7° of ER) in males. The mean angle between CEA and SEA was overall 5.1 +/−1.8° (range, 3.3° to 9.1°), in females 5.1 +/−1.6° (range, 3.5° to 9.0°) compared to 5.0 +/−2.4° (range, 3.2° to 9.1°) in males.

Conclusion: Well-functioning TKA demonstrated a highly variable rotational alignment of the femoral component ranging from excessive external rotation to excessive internal rotation. These findings challenge current reference values for optimal femoral component rotation.

Introduction: Stiffness after primary total knee arthroplasty (TKA) is a severe complication that has been associated with excessive internal rotation of the femoral component.

Methods: Between 2001 and 2004, 18 patients with 18 well-fixed, aseptic primary TKA underwent revision TKA at a single high-volume joint replacement center for stiffness in the presence of femoral component mal-rotation. Stiffness was defined as ROM with less than 90° of maximum flexion or a flexion contracture greater than 10°. Femoral component malrotation was defined as a condylar twist angle of more than 4° of internal rotation using CT scans. Following IRB approval, 17 out of 18 patients (median age at time of the index surgery 62.7 years, range 45 to 78; female, n=11; male, n=6) were available for retrospective outcome assessment. The mean time between primary and revision TKA was 3.2 years (range, 9–79 months). At a mean follow-up of 3.3 years (range, 2 to 6), all patients were evaluated clinically using the Knee Society objective and functional scores, and by CT measurement of femoral component rotation. Patients without additional procedures between primary and index revision TKA (group A, n=9) were compared using Student t-testing with those which had undergone additional interventions (group B, n=8).

Results: Five patients had required additional procedures after the index revision TKA including closed manipulation under anesthesia in one case, patellar resurfacing in one case, metal removal after tubercle osteotomy and open debridement in another case, and tibial component revision followed by revision TKA in one case. CT scans after revision TKA revealed correction of femoral component rotation in all but one case from each group. After revision TKA, the mean objective score was overall 73 points, in group A 82 points compared to 63 points in group B (p< 0.001). In group A there were 78% excellent or good results compared to 13% in group B. The mean function score was overall 74 points, 78 points in group A compared to 69 points in group B. There were 67% good or excellent results in group A compared to 12% in group B. Mean flex-ion increased overall from 71 to 92 degrees (p< 0.01), in group A from 61 to 96 degrees (p< 0.01) and in group B from 82 to 89 degrees. Mean flexion contracture was reduced overall from 7 to 4 degrees, in group A from 6 to 3 degrees, and in group B from 8 to 5 degrees. Stiffness persisted in four cases (24%) (group A, n=1; group B, n=3). Satisfaction (VAS 0–100; 100=completely satis-fied) scored overall a mean of 52 points, in group A 57 points and in group B 44 points.

Conclusion: Overall, revision TKA for knee stiffness associated with femoral component internal malrotation resulted in significantly improved knee motion. However, outcome was less predictable in those patients with additional procedures between primary and revision TKA.