Do Stemmed Tibial Components in Total Knee Arthroplasty Improve Outcomes in Patients With Obesity?

BACKGROUND: Recent clinical studies have reported that patients with higher body mass index (BMI) are more likely to experience premature failure of total knee arthroplasty (TKA), lower knee scores, and perhaps more pain in the prosthetic joint. However, it is not known whether certain implant design features such as tibial stems might be associated with differences in the frequency of tibial pain in patients with higher BMIs. QUESTIONS/PURPOSES: Therefore, it was our aim to compare (1) function and pain (as measured by the New Knee Society Score, Knee Injury and Osteoarthritis Outcome Score [KOOS], and visual analog pain scores); (2) quality of life (as measured by SF-12); and (3) mechanical complications and premature revision (defined as revision before 2 years) between patients with obesity undergoing TKA (BMI > 30 kg/m2) who received either a stemmed or an unstemmed tibial component. METHODS: In this randomized controlled trial, 120 patients with a BMI > 30 kg/m2 scheduled for primary arthritis TKAs and end-stage knee osteoarthritis were included. Patients were stratified into groups defined as moderately obese (BMI 30-35 kg/m2, N = 60) and severely obese (BMI > 35 kg/m2, N = 60) groups. Patients in each stratified subgroup then were randomized to receive either a stemmed (10 mm/100 mm) proximally cemented tibial component or the other, a standard cemented component. Patients were evaluated preoperatively and 2 years after surgery using the new Knee Society Score (KSS), KOOS, SF-12 score, and a visual analog pain score after 100 meters of walking. Although no minimum clinically important differences (MCIDs) have yet been defined for the new KSS, we considered differences smaller than 10 points to be unlikely to be clinically important; the MCID for the KOOS is estimated at 8 to 10 points, the SF-12 to be 4 points, and the visual analog scale to be 2 cm on a 10-cm scale. Patients were followed until death, revision, or for a minimum of 2 years (mean, 3 ± 0.8 years; range, 2-4 years). No patient was lost to followup before 2 years. RESULTS: Although we found that patients treated with stemmed TKAs had higher functional outcomes, the differences were small and unlikely to be clinically important (subjective KSS mean 69 ± 7 points versus 75 ± 7, mean difference 6 points, 95% confidence interval [CI] 2-11, p = 0.03; objective KSS mean 80 ± 6 points versus 85 ± 6 points, mean difference 5 points, 95% CI 0-9, p = 0.01). Compared with patients with a stemmed TKA, patients with a standard implant reported lower KOOS pain subscores (81 ± 9 versus 76 ± 8; p = 0.04) and lower KOOS symptom subscores (74 ± 7 versus 68 ± 7; p = 0.03). The proportions of patients experiencing complications were not different with the numbers available for all groups and subgroups. CONCLUSIONS: Although we detected differences in some patient-reported outcomes scores for pain and function favoring implants with stems, the differences were small and unlikely to be clinically important. Because these stems may have disadvantages, perhaps including difficulty of revision, we cannot draw a strong conclusion in support of their use. LEVEL OF EVIDENCE: Level I, therapeutic study.

Better satisfaction of patients operated on anterior cruciate ligament reconstruction in outpatient setting. A prospective comparative monocentric study of 60 cases.

INTRODUCTION: The purpose of this study was to compare satisfaction, clinical scores, and complications of patients operated on anterior cruciate ligament reconstruction (ACLR) in outpatient setting compared to patients operated in the conventional hospitalization. PATIENTS AND METHODS: This prospective non-randomized study compared 30 patients (mean age 31 ± 9 years) operated on outpatient setting for an isolated ACLR matched 1:1 according to age, gender, body mass index, delay to surgery, and preoperative clinical score (IKDC) to 30 patients operated for an ACLR in our conventional hospitalization department during the same period. All the patients were operated on by the same surgeon. The same technique of anterior cruciate ligament reconstruction with using four bundles semitendinosus and cage fixation was used. The same anaesthesiologic protocol and perioperative cares were used in all patients. Patients' satisfaction was assed using five questions about the course of surgery and hospitalization and a four-level satisfaction questionnaire (excellent, good, fair, and poor). Clinical scores (IKDC and KOOS) were compared preoperatively and at 1 year. Readmission within 30 day and complications at 1 year were compared in both groups. RESULTS: Satisfaction was significantly better in the group of day-case surgery and more patients of the group day-case surgery recommended this modality of treatment (29 against 24; p = 0.04). The IKDC score improved in the two groups (day-case group from 64 ± 17 to 86 ± 7; p < 0.001; conventional hospitalization from 60 ± 21 to 85 ± 10; p < 0.001), but no significant difference between two groups was found at 1 year (p = 0.86). No readmission was necessary in the two groups, but two revisions were needed in the group of the conventional hospitalization. CONCLUSIONS: Results of our study showed that patients operated on day-case surgery for an isolated ACLR presented a higher rate of satisfaction compared to patients operated in the conventional hospitalization with comparable clinical results at 1 year. LEVEL OF EVIDENCE: Level III, comparative study.

No Benefit After THA Performed With Computer-assisted Cup Placement: 10-year Results of a Randomized Controlled Study.

BACKGROUND: Computer-assisted surgery (CAS) for cup placement has been developed to improve the functional results and to reduce the dislocation rate and wear after total hip arthroplasty (THA). Previously published studies demonstrated radiographic benefits of CAS in terms of implant position, but whether these improvements result in clinically important differences that patients might perceive remains largely unknown. QUESTIONS/PURPOSES: We hypothesized that THA performed with CAS would improve 10-year patient-reported outcomes measured by validated scoring tools, reduce acetabular polyethylene wear as measured using a validated radiological method, and increase survivorship. METHODS: Sixty patients operated on for a THA between April 2004 and April 2005 were randomized into two groups using either the CAS technique or a conventional technique for cup placement. All patient candidates for a THA with the diagnosis of primary arthritis or avascular necrosis were eligible for the CAS procedure and randomly assigned to the CAS group by the Hospital Informatics Department with use of a systematic sampling method. The patients assigned to the freehand cup placement group were matched for sex, age within 5 years, pathological condition, operatively treated side, and body mass index within 3 points. All patients were operated on through an anterolateral approach (patient in the supine position) using cementless implants. In the CAS group, a specific surgical procedure using an imageless cup positioning computer-based navigation system was performed. There were 16 men and 14 women in each group; mean age was 62 years (range, 24-80 years), and mean body mass index was 25 ± 3 kg/m(2). No patient was lost to followup at 10 years, but five patients have died (two in the CAS group and three in the control group). At the 10-year followup, an independent observer blinded to the type of technique performed patients' evaluation. Cup positioning was evaluated postoperatively using a CT scan in the two groups with results previously published. At 10 years, we assessed subjective functional outcome and quality of life using validated questionnaires (SF-12, Harris hip score [HHS], Hip injury and Osteoarthritis Outcome Score). Wear rate was then evaluated on standardized radiographs using a previously validated semiautomated computer analogic measurement method (dual circle method). Complications and survivorship were compared between groups. With our available sample size, this study had 80% power to detect a difference of 4 points out of 100 on the HHS at the p < 0.05 level. RESULTS: With the numbers available, we found we found no differences between groups regarding HSS at last followup 95.3 ± 5.9 points (CAS group) versus 96.2 ± 4.5 points, a mean difference of 0.9 points (95% confidence interval [CI], -4.3 to 4.6; p = 0.6). There was no difference between the groups in terms of the mean (± SD) acetabular linear wear at 10 years. The mean wear was 0.71 ± 0.6 mm in the CAS group versus 0.77 ± 0.52 mm in the control group, a mean difference of 0.06 mm (95% CI, -0.1 to 0.2; p = 0.54). With the numbers available, there was no difference between the CAS group and the conventional THA groups in terms of survivorship free from aseptic loosening (100%; 95% CI, 100%-95%, versus 100%; 95% CI, 100%-94%; p = 0.3). CONCLUSIONS: Our observations suggest that CAS used for cup placement does not confer any substantial advantage in function, wear rate, or survivorship at 10 years after THA. Because CAS is associated with added costs and surgical time, future studies need to identify what clinically relevant advantages it offers, if any, to justify its continued use in THA. LEVEL OF EVIDENCE: Level II, therapeutic study.

Anatomical Findings in Patients Undergoing Total Hip Arthroplasty for Idiopathic Femoral Head Osteonecrosis.

BACKGROUND: Osteonecrosis of the femoral head has a host of etiologies. However, in 30% of the cases, no underlying etiology is identified and the process is considered "idiopathic." Our hypothesis was that osseous anatomical abnormalities might be frequently found in patients with femoral head osteonecrosis. METHODS: A retrospective, 1:2 matched, case-control study was undertaken to compare ninety patients with idiopathic osteonecrosis who had undergone lower-limb computed tomography (CT) prior to undergoing total hip arthroplasty with 180 control patients matched for age, sex, and body mass index (BMI) who had undergone lower-limb computed tomography scanning at our radiology department for any reason except articular or bone disease. Preoperative CT scans were performed for all patients to evaluate femoral offset, femoral neck-shaft angle, femoral neck version, femoral head diameter, acetabular coverage estimated with use of the lateral center-edge angle, acetabular version, and acetabular diameter. The mean age was forty-five years, 69% of the patients were men, and the mean BMI was 26 kg/m2. RESULTS: Anatomical "abnormalities" associated with osteonecrosis were determined to be a femoral neck-shaft angle of <129° (likelihood ratio [LR] = 3.6), femoral neck version of >17° (LR = 3.8), a lateral center-edge angle of <32° (LR = 5.7), and acetabular version of <19° (LR = 1.38). A combination of three of the four anatomical "abnormalities" was found in 73% of the patients with osteonecrosis but only 11% of the control cases (LR = 6). CONCLUSIONS: This 1:2 matched, anatomical study suggests that acetabular and femoral anatomical factors, in isolation or combination, can be found in a large percentage of cases of "idiopathic" osteonecrosis. CLINICAL RELEVANCE: In this study, isolated or combined abnormalities of the hip were observed in the group of patients with osteonecrosis. Those elements may help surgeons to understand the process underlying idiopathic osteonecrosis and thus require further investigation.

Balloon tibioplasty for reduction of depressed tibial plateau fractures: Preliminary radiographic and clinical results.

PURPOSE: In vitro studies have shown promising results for balloon-guided inflation tibioplasty. It was our hypothesis that this technique may be safe and effective for use in depressed lateral tibial plateau fracture. METHODS: We performed a prospective study of all patients suffering from a depressed lateral tibial plateau fracture, managed in our institution with inflation tibioplasty and a resorbable calcium phosphate bone substitute injection, between January 2012 and December 2013. Twenty patients, mean age 54.3 ± 12. 8 years, suffering from a depressed lateral tibial plateau fracture (Schatzker type II and III) were included. We then aimed to evaluate at a minimum follow-up of one year: (1) the rate of complications, (2) the clinical outcome (Knee Injury and Osteoarthritis Outcome (KOO) and 12-Item Short Form Health Survey (SF-12) scores); and (3) the radiographic outcome (evaluated by CT-scan). RESULTS: No peri-operative complications occurred. In one patient, calcium phosphate substitute was found in the infrapatellar fat pad on post-operative radiography with no clinical or radiographic consequences at one year. At one year after surgery, the KOO subscores were: Pain 80 (range 64-93), other symptoms 81.3 (69-93), daily living activities 81.9 (46-99), sport 65.83 (20-100), and quality of life 67.04 (31-100). The SF-12 activity component was 40.4 (28.6-52.2) and SF-12 mental component 47.71 (28 - 67.1). The mean depressed step-off of the lateral joint decreased from 10.7 ± 4.8 mm pre-operatively to 2.7 ± 1.7 mm post-operatively (p < 0.0001). CONCLUSION: Our observations suggest that the use of balloon-guided inflation tibioplasty with injection of a resorbable bone substitute is safe, and results in a high rate of anatomic reduction and good clinical outcomes in patients with depressed tibial plateau fractures. LEVEL OF EVIDENCE: Therapeutic Level IV.

The John Insall Award: No Functional Benefit After Unicompartmental Knee Arthroplasty Performed With Patient-specific Instrumentation: A Randomized Trial.

BACKGROUND: Component alignment can influence implant longevity as well as perhaps pain and function after unicompartmental knee arthroplasty (UKA), but correct alignment is not consistently achieved. To increase the likelihood that good alignment will be achieved during surgery, smart tools such as robotics or patient-specific instrumentation (PSI) have been introduced. QUESTIONS/PURPOSES: We hypothesized that UKA performed with PSI would result in improved level gait as ascertained with three-dimensional analysis, implant positioning, and patient-reported outcomes measured by a validated scoring system when compared with conventional instrumentation 3 months and 1 year after surgery. METHODS: We randomized 60 patients into two groups using either the PSI technique or a conventional technique. All patients were operated on using the same technique and the same cemented metal-backed implant. Mean age of the patients was 63 ± 4 years (range, 54-72 years) and mean body mass index was 28 ± 3 kg/m(2). Patients were evaluated preoperatively, at 3 months, and 1 year after surgery by an independent observer blind to the type of technique. Gait parameters were assessed with three-dimensional analysis during level walking preoperatively and at 1 year, frontal and sagittal position of the implant was evaluated on full-length radiographs at 3 months, and subjective functional outcome and quality of life using routine questionnaires (SF-12, new Knee Society Score [KSS], Knee Injury and Osteoarthritis Outcome Score) at 3 months and 1 year. This study had 80% power to detect a 15% difference in walking speed at the p < 0.05 level. RESULTS: One year after surgery, there were no differences between the two groups in the analyzed gait spatiotemporal parameters, respectively, for PSI UKA and conventional UKA : double limb support 31% (25%-54%) versus 30% (23%-56%; p = 0.67) and walking speed (1.59 m/s [0.86-1.87 m/s] versus 1.57 m/s [0.71-1.96 m/s]; p = 0.41). No difference was observed between the two groups in terms of lower limb alignment (PSI group 178° ± 3°, conventional group 178° ± 4°; p = 0.24) or implant positioning on mediolateral and anteroposterior radiographs. There were no differences in the functional score between the PSI and conventional TKA groups at 3 months and 1 year after surgery: KSS objective knee scores (PSI: 85 ± 8 points at 3 months, 87 ± 5 points at 1 year and conventional instrumentation: 82 ± 8 points at 3 months 83 ± 6 points at 1 year; p = 0.10) and functional activity scores were similar in both group (PSI: 71 ± 12 points at 3 months and 74 ± 7 points at 1 year versus conventional group: 73 ± 11 points at 3 months and 75 ± 6 at 1 year; p = 0.9). CONCLUSIONS: Our observations suggest that PSI may confer small, if any, advantage in alignment, pain, or function after UKA. This argument can therefore not be used to justify the extra cost and uncertainty related to this technique. LEVEL OF EVIDENCE: Level I, therapeutic study.

Is isolated insert exchange a valuable choice for polyethylene wear in metal-backed unicompartmental knee arthroplasty?

PURPOSE: The aim of this study was to evaluate the clinical outcome and survival rate after isolated liner exchange for polyethylene (PE) wear in well-fixed metal-backed fixed-bearing unicompartmental knee arthroplasty (UKA). METHODS: Twenty medial UKAs in 19 patients [mean age 68.7 years ± 8.7 (range 48.5-81.5 years)] operated on for a direct PE liner exchange after isolated PE wear between 1996 and 2010 in two institutions were retrospectively reviewed. The mean delay between the index operation and revision was 8.2 years ± 2.6 (range 4.8-12.8 years). A four-level satisfaction questionnaire was used, and clinical outcomes were assessed using Knee Society scores (KSS) and range of motion (ROM) evaluation. Radiological evaluation analysed the position of the implants and progression of the disease. Survival rate of the implants was evaluated using Kaplan-Meier analysis with two different end-points. RESULTS: At the last follow-up [mean 6.8 years ± 5.2 (range 1.1-15.9 years)], 15 patients (79 %) were enthusiastic or satisfied. KSS improved from 73.4 to 86.4 points (p = 0.01) and function from 58.9 to 89.2 points (p < 0.001). ROM at last FU was 126.5° ± 10.3°. The survival rate at 12 years considering "revision for any reason" as the end-point was 71.3 ± 15.3 %, and the survival rate at 12 years considering "revision of UKA to TKA" as the end-point was 93.3 ± 6.4 %. CONCLUSION: Isolated liner exchange for PE wear in well-fixed metal-backed fixed-bearing UKA represents a valuable treatment option in selective patients with durable improvement of clinical outcomes without compromising any future revision. LEVEL OF EVIDENCE: Retrospective therapeutic study, Level IV.

Are titanium-on-titanium TiAl6V4 modular necks safe in total hip arthroplasty for non-overweight patients? Results of a prospective series at a minimum follow-up of 7 years.

Using extramedullar modularity in total hip arthroplasty has been proposed as an option to optimize the restoration of hip biomechanics. To avoid the problems that were observed with cobalt-chrome modular neck, titanium modular necks have been developed. The goals of our study were to evaluate the safety of titanium-on-titanium TiAl6V4 modular neck system. Hundred patients with a mean age of 69.6 ± 10.6 (42-86 years) and mean BMI of 25.07 ± 4.86 (17-38 kg/m(2)) suffering from primary or secondary arthritis of the hip were prospectively included. At a minimum of 7 years, no fracture of the modular neck was observed. No patient required a revision. No sign of loosening was found in the radiological analysis. Our study shows that titanium-on-titanium TiAl6V4 modular neck system can safely be used with good midterm clinical and radiological results for non-overweight patients. These results should be confirmed at longer follow-up.

Are Revisions of Unicompartmental Knee Arthroplasties More Like a Primary or Revision TKA?

If revision is required, most unicompartmental arhroplasties (UKAs) are converted to total knee arthroplasties (TKAs) and conflicting results regarding surgical complexity and outcome have been reported in publications. 48 UKAs converted to a TKA between 1998 and 2009 were matched based on age, gender, and body mass index, pre-operative Knee Society Score, length of follow-up, and date of the index surgery to 48 primary TKAs and 48 revision TKAs. Surgical characteristics, clinical outcomes, and complications were compared at a mean follow-up of 7 ± 4 years. Even if a revision of UKA is technically less demanding than a revision TKA, functional scores, quality of life, complications and survival rate after revision UKA are more comparable to a revision than primary TKA.

A bullet in the supraspinatus compartment successfully removed by arthroscopy: case report and review of the literature.

Arthroscopic removal of bullet from intra-articular compartment has been described for several joints. Only few reports dealing with this condition in the shoulder have been reported especially for the glenohumeral and the subacromial compartments. We report the story of a fifty-seven-year-old man presenting a bullet in the supraspinatus compartment of his left shoulder successfully removed by arthroscopy.

Lower function, quality of life, and survival rate after total knee arthroplasty for posttraumatic arthritis than for primary arthritis.

BACKGROUND AND PURPOSE: Total knee arthroplasty (TKA) for treatment of end-stage posttraumatic arthritis (PTA) has specific technical difficulties and complications. We compared clinical outcome, postoperative quality of life (QOL), and survivorship after TKA done for PTA with those after TKA performed for primary arthritis (PA). PATIENTS AND METHODS: We retrospectively reviewed patients who were operated on at our institution for PTA between 1998 and 2005 (33 knees), and compared them to a matched group of patients who were operated on for PA during the same period (407 knees). Clinical outcomes and postoperative QOL were compared in the 2 groups using Knee Society score (KSS), range of motion (ROM) of the knee, and the knee osteoarthritis outcomes score (KOOS). Implant survival rate was calculated using Kaplan-Meier analysis. RESULTS: At a mean follow-up of 11 (5-15) years, KSS knee increased from mean 39 (SD 18) to 87 (SD 16) in the PA group (p = 0.003), and from 31 (SD 11) to 77 (SD 15) in the PTA group (p = 0.003). KSS function increased from 55 (12) to 89 (25) in the PA group (p = 0.008) and from 44 (SD 14) to 81 (SD 10) in the PTA group (p = 0.008). Postoperative ROM also improved in both groups, from 83° to 108° in the PTA group (p < 0.001) as opposed to 116° to 127° in the PA group (p = 0.001), with lower results in the PTA group (p < 0.001). KOOS was lower in the PTA group (p < 0.001). The survival rate of TKA at 10 years with an endpoint defined as "any surgery on the operated knee" showed better results in the PA group (99%, CI: 98-100 vs. 79%, CI: 69-89; p < 0.001). INTERPRETATION: Patients and surgeons should be aware that clinical outcome and implant survival after TKA for PTA are lower than after TKA done for PA.

Are revisions of patellofemoral arthroplasties more like primary or revision TKAs.

BACKGROUND: Patellofemoral arthroplasty (PFA) can be considered in patients with patellofemoral disease. However, the use of partial arthroplasty often causes concern among clinicians and patients that revision to total knee arthroplasty (TKA) will be needed and, if so, whether this revision will be straightforward or more complicated. QUESTIONS/PURPOSES: We set out to determine if conversion of a PFA to a TKA was more similar to a primary or to a revision TKA in terms of surgical characteristics, knee scores, range of motion, and complications. METHODS: Between 2001 and 2008, we revised 21 PFAs to TKAs, all of which were available for followup at a minimum of 5 years (median, 6 years; range, 5-12 years). These patients were matched one-to-one by age, sex, body mass index, length of followup, and preoperative Knee Society Scores (KSS) to 21 primary and 21 revision TKAs. We analyzed operative time and amount of blood loss. Clinical outcomes assessed were range of motion and KSS. RESULTS: Blood loss (405 mL versus 460 mL versus 900 mL; odds/hazard ratio, 1.33, 95% confidence interval [CI], 0.3-5.85; p=0.14 for primary TKA versus revision PFA and odds/hazard ratio, 0.13, 95% CI, 0.03-0.52; p<0.01 for revision PFA versus revision TKA) and operative time (52 minutes versus 72 minutes versus 115 minutes; odds/hazard ratio, 5.45, 95% CI, 1.23-27.4; p=0.02 for primary TKA versus revision PFA and odds/hazard ratio, 0.5, 95% CI, 0.01-0.44; p<0.001 for revision PFA versus revision TKA) were not different between the primary TKA and revision PFA groups but higher in the revision TKA group. KSS (knee and function) were higher in the primary TKA group (92 [range, 60-100] and 91 [range, 65-100]) than they were in the revision PFA (85 [range, 40-100] and 85 [range, 30-100]) and revision TKA groups (75 [range, 30-100] and 68 [range, 25-100]; p<0.001). Flexion was better in the primary TKA (125 [range, 105-130]) and revised PFA (120 [range, 100-130]) groups than the revision TKA group (105 [range, 80-115]; p=0.0013). There were more complications in the revision PFA group (two of 21) compared with the primary TKA group (zero of 21, p=0.005) but not compared with the revision TKA group (three of 21; p=0.85). CONCLUSIONS: With the numbers available, we found that revising a PFA is comparable to a primary TKA in regard to surgical characteristics and postoperative clinical outcomes (including knee scores and range of motion), and both are superior to revision TKA, although the frequency of complications was higher in the revision PFA group than it was in the primary TKA group. The majority of patients undergoing revision of a PFA to a TKA can be treated with a standard implant. LEVEL OF EVIDENCE: Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Unexpected wear of an unicompartimental knee arthroplasty in oxidized zirconium.

Unicompartimental knee arthroplasty is a successful procedure for the treatment of localized osteoarthritis to one compartment of the knee with good long-term results. However, several modes of failure of unicompartimental knee arthroplasty have been described, namely aseptic or septic loosening, progression of disease, wear, and instability. Metallosis after unicompartimental knee arthroplasty is rarely reported and is most often related with polyethylene wear or break. We report on a case of rapid failure of unicompartimental knee arthroplasty in oxidized zirconium associated with metallosis secondary to the dislocation of the polyethylene.

Fracture of the lateral process of the talus: a report of two cases.

Fracture of the lateral process of the talus is a rare lesion commonly described in snowboarding injuries. Nevertheless, several conditions can lead to this injury, which is often misdiagnosed as a severe ankle sprain because of the difficulty in detecting it on standard radiographic views. Computed tomography is very helpful for the assessment of this injury. The type of treatment will depend on the size and degree of the displacement of the fracture. This injury can also lead to subtalar joint osteoarthritis. We report 2 cases of fracture of the lateral process of the talus. In the first case, a young male sustained a combined inversion and dorsiflexion strain of his right foot when he fell from a ladder. In the second case, a woman broke the lateral process of her right talus by the same mechanism when she was sledding. In the 2 situations, we opted for an open reduction and internal fixation using 2.4-mm cannulated screws. Both patients were allowed walking with partial weightbearing with a walker boot (VACOped(®)) for 6 weeks. At 1 year, both showed a consolidated fracture and had regained their preinjury level of activity.