Introduction

The demands placed upon joint surgeons are perhaps greatest when treating the revision arthroplasty patient, who present with complications demanding skill in diagnosis and evaluation, interpersonal communication and the technical aspects of the revision procedure. However, little information exists identifying which specific tasks in revision arthroplasty are most difficult for surgeons to master, and whether the greatest challenges arise from clinical, cognitive or technical facets of patient treatment. This study was undertaken to identify which tasks associated with revision total knee replacement (TKR) are perceived as most challenging to young surgeons and trainees to guide future efforts in surgical training and curriculum development.

Instability in flexion after total knee replacement (TKR) typically occurs as a result of mismatched flexion and extension gaps. The goals of this study were to identify factors leading to instability in flexion, the degree of correction, determined radiologically, required at revision surgery, and the subsequent clinical outcomes. Between 2000 and 2010, 60 TKRs in 60 patients underwent revision for instability in flexion associated with well-fixed components. There were 33 women (55%) and 27 men (45%); their mean age was 65 years (43 to 82). Radiological measurements and the Knee Society score (KSS) were used to assess outcome after revision surgery. The mean follow-up was 3.6 years (2 to 9.8). Decreased condylar offset (p < 0.001), distalisation of the joint line (p < 0.001) and increased posterior tibial slope (p < 0.001) contributed to instability in flexion and required correction at revision to regain stability. The combined mean correction of posterior condylar offset and joint line resection was 9.5 mm, and a mean of 5° of posterior tibial slope was removed. At the most recent follow-up, there was a significant improvement in the mean KSS for the knee and function (both p < 0.001), no patient reported instability and no patient underwent further surgery for instability.

The following step-wise approach is recommended: reduction of tibial slope, correction of malalignment, and improvement of condylar offset. Additional joint line elevation is needed if the above steps do not equalise the flexion and extension gaps.

Cite this article: Bone Joint J 2014;96-B:1644–8.

Purpose: Femoroacetabular impingement (FAI) is recognized as an etiological risk factor for hip arthritis. The potential for joint preserving surgical techniques that may delay the progression to early arthritis and retard the possibility of arthroplasty at a young age is promising. This study presents the outcome of surgical treatment of FAI through a less invasive technique performed through a modified Smith-Peterson approach without hip dislocation, or arthroscopy.

Method: Using an institutional database, a total of 72 patients (80 hips) with radiographic and clinical diagnosis of FAI who underwent direct anterior femoroacetabular osteoplasty (FAO) were identified. Preoperative and postoperative functional evaluation was performed on these patients. The operative findings were recorded in detail and evaluated with regard to outcome.

Results: Intraoperative diagnosis of labral tear and osteochondral lesions in the anterosuperior acetabulum was confirmed in all cases. The surgical approach provided adequate access to allow labral repair and osteoplasty of the femoral neck and the acetabulum, whenever needed. There were no intraoperative complications. All patients experienced a significant improvement in function as measured by modified Harris hip and SUSHI scores. Majority (85%) of the patients were satisfied with the outcome of the surgery. In addition, Health Survey SF-36 showed most patients felt their health had improved significantly. The predictors of poor outcome were previous hip scope, lack of labrum for repair, large chondral lesions, and workman’s compensation status.

Conclusion: This study presents the early results of a less invasive surgical treatment for femoroacetabular impingement. This ongoing study shows that the described technique seems to be a viable approach for treatment of this painful condition in the young.

Periprosthetic infection (PPI) remains the most dreaded and difficult complication of total joint arthroplasty. Although there is no definite diagnostic test for PPI, synovial leukocyte count and neutrophil percentage have been reported to have high sensitivity and specificity. However, leukocytes and neutrophils introduced into the joint during a traumatic aspiration can skew results and undermine the predictive value of this diagnostic test. This study intends to determine the diagnostic value of implementing a corrective formula frequently used in traumatic spinal taps to adjust for serum leukocytes introduced into the joint fluid during a bloody tap.

We conducted a review of all TKA aspirations of infected and non-infected patients performed at our institute from 2000 to 2005.

The following inclusion criteria were used:

(a) a red cell count (RBC) was performed on the aspirate, and

Patients with inflammatory arthropathy or those who underwent reimplantation after PPI were excluded. Strict criteria for diagnosis of PPI were used. We previously determined at our institute the cut-off values for fluid leukocyte count (> 1760 cells/μl) and neutrophil percentage (> 73%).

The adjusted fluid leukocyte counts were calculated using the following formula:

Wadjusted = WBCobserved – [(WBCblood * RBC-fluid/RBCblood)] predicted.

A similar formula was implemented to calculate the adjusted absolute neutrophil counts.

Our cohort included 73 infected and 32 aseptic total knee arthroplasties that fulfilled the above criteria. After correcting for introduced red blood cells, cell counts of 3 infected patients dropped below the cut-off value, while the remaining 70 maintained a high cell count. However, the 3 infected patients had initial cell counts below our reported cut-offs. Of the 32 non-infected patients, 10 patients had false positive cell counts due to the presence of extremely high numbers of blood RBC. Five of the 10 false positive aspirates successfully corrected to levels below the thresholds used to diagnose infection. The aspirates that corrected had a greater number of introduced RBCs, an initial higher cell count, and 20 times more fluid WBC deducted from the initial cell count.

The corrective formula can safely adjust for RBC found in a traumatic tap and detect false positive results among non-infected TKA without compromising the diagnosis of infection. Adjusted aspirates of non-infected TKA can be expected to decrease below zero due to one of the following: adherence of the introduced systemic WBC to the joint synovium, greater rate of lysis of the introduced systemic WBC compared to the systemic RBC, laboratory errors in performing fluid cell counts.

Periprosthetic infection (PPI) is one of the most devastating complications of total knee arthroplasty (TKA). It is widely accepted that resection arthroplasty supplemented with intravenous antibiotics and delayed exchange arthroplasty is the treatment modality of choice for infected TKA. However, the outcome after reimplantation has varied and unpredictable results have been reported. This study evaluates the outcome of this treatment strategy in a single high volume specialised center. Furthermore, our study aims to identify the factors that lead to failure of this treatment.

A thorough review of our joint registry database revealed that 80 patients with an infected TKA underwent resection arthroplasty at our institution during 2000–2005. Sixty-five patients underwent two-stage exchange arthroplasty while the remaining 15 failed to have the second stage reimplantation due to ill health or underwent arthrodesis or amputation. The latter 15 were excluded from the analysis. All patients were followed up prospectively for at least two years. Detailed data including demographics, comorbidities, surgical history, and medication intake was collected. Intraoperative data, organism profile, and complications were also documented. Failure was defined as patient requiring additional surgical procedure for control of infection or loosening.

Two-stage exchange arthroplasty successfully eradicated infection in 45 patients (31%) without need for further treatment. Twelve patients (18%) had recurrent infection that necessitated another resection arthroplasty. Eleven (17%) patients required irrigation and debridement for postoperative purulent drainage which successfully treated infection in 5 cases (46%). The remaining 6 patients failed and required resection arthroplasty. Three additional patients had early loosening of components and required revision arthroplasty. The exact cause of loosening in these patients could not be determined, and despite lack of isolation of organisms infection was suspected. Our analysis identified that irrigation and debridement prior to resection arthroplasty are major risk factors for failure.

Current strategies to treat periprosthetic infection remain imperfect. Two-stage exchange arthroplasty with all its inherent problems and inconveniences imparted a modest success in treatment of PPI at our high volume specialised center. The rise in the number of resistant and virulent organisms, increase in the number of patients with severe medical comorbidities who develop infection may account for the decline in the success of two-stage resection arthroplasty. Novel strategies for treatment of PPI are desperately needed.

Background: Vascular injuries associated with total joint arthroplasty are the most feared complication. The arterial and venous injury can occur due to direct or indirect trauma. A high index of suspicion, recognition of the injury and prompt treatment, with the immediate availability of a vascular surgeon is vital for good outcome.

Methods: Using prospectively collected data on 13624 patients undergoing total joint arthroplasty at our institution, all incidences of vascular injury were identified. Detailed data regarding the mode of presentation, the type and the outcome of intervention delivered, and the eventual functional outcome of the total joint arthroplasty were determined.

Results: There were a total of 17 vascular injuries (0.1%). Majority (16/17) of these vascular injuries were detected in the postoperative recovery area. 9 injuries occurred after TKA and 8 occurred after THA. Indirect injury was the mechanism in TKA patients with popliteal artery thrombosis being the mechanism. In contrast direct injury was the mechanism in THA patients. Fasciotomy was performed in all TKA patients and none were needed in the THA patients. One patient died of complications related to vascular injury. 12 of 17 patients (70%) had launched a legal suit against the operating surgeon.

Conclusions: After more than 80 years of accumulated experience and more than 35000 joint replacements performed by 5 surgeons in our center, the vascular complication still continues to occur. Patient awareness regarding this real problem may play a role in defraying the extremely high likelihood of legal suits associated with this complication.

Introduction: Pulmonary embolism (PE) is a potentially fatal complication of total joint arthroplasty (TJA). Therefore, reliable means for diagnosis and evaluation of severity is essential. This study evaluates the reliability of common clinical signs and symptoms in the diagnosis of PE. In addition, clinical presentation is correlated with size and location of emboli within the pulmonary vasculature (segmental, lobar, or main).

Methods: The clinical and imaging records of all patients with confirmed diagnosis of PE following TJA performed between 2000 and 2004 were reviewed in detail. The mode of presentation and the subsequent imaging findings were noted.

Results: A total of 132 confirmed PE cases were studied. Clinical presentation included dyspnea (19.7%), chest pain (7.6%), change of mental status (6.8%0, hypotension (6.1%), and diaphoresis (3.8%). Mean room air pulse-oximetry was 85.5%. Arterial sampling showed mean O2 saturation of 88.1% and pO2 of 58.7. There was not a direct correlation between the size of the PE and the clinical presentation. However, there was a correlation between the severity of oxygen desaturation and the size and location of the embolus.

Conclusions: The presentation of PE can be non-specific and highly variable ranging from mild dyspnea to catastrophic hemodynamic collapse. Common clinical signs have a low sensitivity for diagnosis and do not correlate with severity of disease. The only correlation seemed to be measured arterial O2 saturation and pressure. Thresholds for the diagnosis of clinically significant pulmonary embolisms need to be established to improve management of this important condition.

Background: Total joint arthroplasty (TJA) is a successful procedure. With the demographic tendency towards an elderly society and a relatively high prevalence of arthritis, the number of joint replacement in the US will increase dramatically in the upcoming years. The orthopaedic surgeons need to be aware of the various types of complications in the early hospital setting associated with elective TJA.

Methods: This prospective study reviewed the systemic and local early complications occurring after 13133 TJA which included 7,438 hip arthroplasties (6,010 primary and 1,428 revisions) and 5,695 knee replacements (4,944 primary and 751 revisions). A standardized and detailed form intended to capture all medical and orthopedic complications was devised, plus a full-time research fellow was dedicated to this study. The hospital course of every patient was followed on a daily basis closely. The circumstances leading to the complications and the details of the therapeutic intervention for each complication were recorded.

Results: In general the incidences of complications were higher following TKA compared to THA. There was 26(0.19%) deaths in the cohort that occurred within 10 days after surgery. 329 major (life threatening) complications occurred in the cohort that included myocardial infarction (36), hypotensive crisis (11), pulmonary embolus (145), tachyarrhythmia (93), pulmonary edema (10), acute renal failure (24), stroke (6), bowel obstruction or perforation (3), and pneumothroax (1). There were 37 major local complications. 301 (91%) of these complications occurred within 4 days of index surgery. There were 453 minor systemic complications, mostly related to anemia, and 99 minor local complications in this cohort.

Conclusions: Total joint arthroplasty despite its success can be associated with serious and life threatening complications. The introduction of MIS surgery and the potential for very early discharge of patients undergoing arthroplasty needs to be scrutinized in light of these findings.