Single Orthopaedic Centre Research Articles

No shortening of the patellar tendon during two-stage total knee arthroplasty revision using articulating spacers.

Surgical techniques in two-stage revision total knee arthroplasty(rTKA) include the use of articulating spacers and static spacers. Shortening of the patellar tendon could be a reason for inferior functional outcomes in two-stage septic rTKA. The aim of this study was to determine if articulating spacers also have negative effects on the extensor mechanism in rTKA. This retrospective study includes 65 consecutive patients (23 women, 42 men, age 71.3 ± 1.2; range, 51.2-88.6 years) undergoing septic two-stage rTKA using an articulating spacer between 2014 and 2021 in a single orthopedic center. For all patients, calibrated true lateral radiographs before total knee arthroplasty (TKA) explantation (T0), directly after TKA explantation (T1), shortly before TKA reimplantation (T2) and 6-8 days after TKA reimplantation (T3) were used to calculate the modified Insall Salvati ratio (mISR). Overall, the mISR decreased significantly immediately after explantation (T0 vs. T1, p = 0.002) from 1.43 ± 0.03 to 1.36 ± 0.03 and remained stable until T2 (1.37 ± 0.02, p = 0.74). Following TKA reimplantation, the mISR increased again to 1.43 ± 0.03 (T3). There were no significant differences between T0 and T3 (p = 0.88). Six out of 65 patients (9%) experienced patellar tendon shortening > 10% at T3. Septic two-stage revision TKA using an articulating spacer does not lead to patellar tendon shortening in the majority of cases. This study suggests that one reason for the improved range of motion after reimplantation may be the use of articulating spacers compared to static spacers.

Cemented and hybrid total hip arthroplasty lead to lower blood loss in primary total hip arthroplasty: a retrospective study.

Little scientific evidence exists on blood loss and transfusion rates depending on the fixation technique. The hypothesis of this study was that the blood loss and transfusion rate are lower in cemented and hybrid total hip arthroplasty (THA) compared to cementless THA. We retrospectively compared a total of 1500 patients who received either cementless, cemented, hybrid or reverse hybrid THA. All patients underwent THA in 2021 at a single orthopedic center in Germany. The lowest blood loss was found in patients who received a fully cemented THA (695 ± 74ml). Hybrid THA with a cemented stem showed a blood loss of 845 ± 30ml and reverse hybrid THA showed the highest blood loss with an average of 994 ± 74ml. Cementless THA caused an average blood loss of 957 ± 16ml. There was a significant difference between cementless THA, hybrid THA (cemented stem), and fully cemented THA (p < 0.05). Transfusion rates ranged from 1.3% (cementless THA) to 7.9% (cemented THA) between the groups with a transfusion rate of 2.5% overall. We found significantly lower blood loss in cemented THA and hybrid THA compared to cementless THA. Although blood loss was lower in cemented and hybrid THA, this did not result in lower transfusion rates. This could be due to other confounders such as age, comorbidities, and preoperative anemia.

Does stem profile have an impact on the failure patterns in revision total knee arthroplasty?

IntroductionRevision total knee arthroplasty (RTKA) has been increasing continuously. The results of RTKA still remain unsatisfactory. Failure patterns and risk factors in RTKA were thoroughly analyzed, with periprosthetic joint infections (PJI) and aseptic loosening remaining at the forefront of re-revision (ReRTKA) causes. While there is evidence that stem profile impacts the revisability of cemented implants, its association with the modes of RTKA failure is unknown.Methods50 consecutive ReRTKA performed in a single orthopedic center during 2016–2017 were retrospectively analyzed. The cases were stratified according to age, sex, number of preexisting revisions, fixation technique, stem design and causes of re-revision. All explanted implants with conical vs. cylindrical stem profiles were compared.ResultsMean age was 67 ± 11.5, and 54% were females. 72% of the cases had ≥ 3 previous revisions. 88% were full-cemented, 3% hybrid and 9% press-fit stems. 36% of the RTKA had conical, 58% cylindrical and 6% combined stem profiles. 92% of the RTKA components were removed. Removal causes were: PJI (52.2%), aseptic loosening (34.8%), implant malposition (9.8%), painful knee (1.1%) and instability (2.2%). While the overall RTKA failure patterns were equally distributed between conical and cylindrical stems, subgroup analysis of only cemented ReRTKA revealed a higher incidence of aseptic loosening within cylindrical stem profiles (46.7% vs. 25.7%, P = 0.05).ConclusionStem profile may have an impact on the process of aseptic loosening in cemented non-metaphyseal engaging RTKA, with cylindrical designs tending to worse outcomes than conical designs. Large cohort studies could provide more clarity on current observation.

General, spinal or regional anaesthesia does not affect strength performance 6 months after ACL reconstruction

PurposeThe recovery of strength is a key element in successfully returning to sports after ACL reconstruction. The type of anaesthesia has been suspected an influential factor in the post-operative recovery of muscle function.MethodsIn this retrospective analysis, n = 442 consecutive patients undergoing primary isolated ACL reconstruction using a hamstring autograft were analysed by pre- and post-operative isokinetic tests in a single orthopaedic centre. These were subdivided into four cohorts: (1) general anaesthesia (n = 47), (2) general anaesthesia with prolonged (48 h) on-demand femoral nerve block (n = 37), (3) spinal anaesthesia (n = 169) and (4) spinal anaesthesia with prolonged (48 h) on-demand femoral nerve block (n = 185). Primary outcome was the change from pre- to post-operative isokinetic strength during knee extension and flexion.ResultsUsing one-way ANOVA, there was no significant influence of the type of anaesthesia. The main effect of anaesthesia on change in extension forces was not significant, and effect sizes were very small (n.s.). Similarly, the main effect of anaesthesia on change in flexion forces was statistically not significant (n.s.).ConclusionsThe findings of this study support the interpretation that the type of anaesthesia has no significant effect on the ability to recover thigh muscle strength 6 months after isolated hamstring ACL reconstruction. With regard to the recovery of athletic performance and return-to-sports testing criteria, there is no reason to avoid regional anaesthesia.Level of evidenceIII.

Periprosthetic Joint Infections Caused by Candida Species-A Single-Center Experience and Systematic Review of the Literature.

Background: The aim of this study was to analyze the treatment results of fungal periprosthetic joint infections (PJI) caused by Candida species from a single orthopedic center and to compare them with reports from other institutions. Methods: Eight patients operated on from January 2014 to December 2021 met the inclusion criteria and were analyzed in terms of clinical outcomes. A systematic review of the literature identified 153 patients with Candida PJIs extracted from 12 studies according to the PRISMA (Preferred Reporting Item for Systematic Reviews and Meta-Analyses) guidelines. Results: The success rate of the treatment in the case series was 50%. The most frequent pathogens were Candida albicans (three cases; 37.5%) and Candida parapsilosis (three cases; 37.5%). In one patient (12.5%), bacterial co-infection was noted, and in five patients (62.5%) significant risk factors of PJI were confirmed. The overall success rate on the basis of data collected for systematic review was 65.5%. A sub-analysis of 127 patients revealed statistically significant differences (p = 0.02) with a higher success rate for the knees (77.6%) than for the hips (58%). In 10 studies the analysis of risk factors was performed and among 106 patients in 77 (72.6%) comorbidities predispose to fungal PJI were confirmed. Bacterial co-infection was noted in 84 patients (54.9%). In 93 patients (60.7%) Candida albicans was the culprit pathogen, and in 39 patients (25.5%) Candida parapsilosis was the culprit pathogen. Based on these two most frequent Candida species causing PJI, the success rate of the treatment was statistically different (p = 0.03), and was 60.3% and 83.3%, respectively. The two-stage strategy was more favorable for patients with Candida parapsilosis infections (94.4% success rate) than the one-stage protocol (50% success rate; p = 0.02); as well as in comparison to the two-stage treatment of Candida albicans (65% success rate; p = 0.04). Conclusions: The analysis of the literature showed no differences in the overall success rate between one- and two-stage surgical strategies for all Candida species, but differed significantly comparing the two most frequent strains and concerning PJI localization. The frequent presence of bacterial co-infections makes it necessary to consider the additional administration of antibiotics in the case of fungal PJI.

Infection complicating 794 primary and revision arthroscopies. Accuracy of actual prophylactic procedures against infection and results from a single orthopedic center in Poland

Abstract Introduction Septic arthritis after arthroscopy (SAAA) is a devasting complication which reported frequency varies about 0.04%–5.7%. The aim of the study is to analyze frequency of SAAA at one orthopedic center, risk factors and accuracy of actual prophylactic measures. Materials and Methods A retrospective study (level of evidence: V) includes 794 (665 primary and 129 revision) “clean” arthroscopies performed in the years 2017–2018 with confirmed joint infection during 30 days after operation without the use of non-resorbable implants and up to 1 year after procedures with non-resorbable implants. Demographic and medical data about potential risk factors of SAAA were analyzed: patients age, sex, operated joint, type of procedure, primary or revision procedure, the use of drains, usage of non-absorbable implant, time of surgery, BMI, time lapse from index operation to diagnosis of SAAA, length of hospital stay, causative microorganisms. All operations were performed by eight different but experienced surgeons, in operation theatre with vertical laminar flow with the capacity of 50 air exchanges per hour. The perioperative antibiotic prophylaxis consisted of one preoperative dose 1 g cefazolin in simple arthroscopies, which was prolonged to 24 hours with 3 doses in cases of implantation of non-absorbable implant (55.8% of patients). Results From 794 cases 4 have been infected: 2 after knee arthrolysis, one after ACL reconstruction and one after rotator cuff repair. There were 2 early, with manifestation within 30 days, and 2 late-onset SAAA. Infections occurred in 0.5% of all arthroscopies and in 0.47% of knee arthroscopies alone. Patients age and time of surgery have not been found significantly different in infected and non-infected cases, whereas age and time of surgery have been significantly different in revision and non-revision cases. Conclusions Primarily aseptic arthroscopic procedures performed with respect to actual perioperative preventive measures have a low risk of postoperative septic arthritis. The risk increases with patients age and time of operation, but not significantly.

233 Blood Tests and Radiographs After Hip and Knee Arthroplasty – We May Not Always Need Them

Abstract Aim Routine blood tests and radiographs are routinely performed after total joint arthroplasty as a pre-discharge requirement. This study aims to explore whether there might be sub-group of patients undergoing arthroplasty for whom post-operative blood tests and radiographs might not be mandated in the absence of clinical concern. Method A retrospective study of 612 ASA 1 and 2 patients underwent total hip or knee arthroplasty at a single orthopaedic centre. Variables purported to be of interest were sodium and Potassium levels, Haemoglobin concentration and eGFR. Return to theatre and alterations of the routine Physiotherapy rehabilitation were matched to post-operative radiographs. Results 42 (6.9%) patients had post-operative haemoglobin below 10 g/L. Of these 4 were symptomatic, which required treatment. Acute kidney injury was identified in 13 patients (2.1%); 11 had pre-existing renal disease. The other two had both suffered pro-longed post-operative hypotension. Two patients had severe hyponatraemia and one of whom had pre-existing renal disease. Two patients had hypokalaemia and one of whom had metabolic syndrome but normalised within 24 hours after oral supplement. No patient had abnormal post-operative radiography that altered management. Conclusions Our study indicates that routine post-operative blood tests and radiographs may not be necessary in ASA 1 and 2 patients with normal pre-existing blood tests. Where patient is clinically symptomatic or there is evidence of pre-operative renal dysfunction, metabolic syndrome, electrolyte imbalance or anaemia, we would suggest blood tests are necessary. If there is no surgical concern, it is safe to delay check radiography until their first post-operative follow up.

Risk Factors for the Occurrence and Progression of Posttraumatic Elbow Stiffness: A Case-Control Study of 688 Cases.

Background: Elbow stiffness is a severe complication after trauma. Surgical or conservative treatments may be ineffective for restoring functional elbow motion. We aim to evaluate intrinsic and extrinsic factors for the occurrence and severity of elbow stiffness.Methods: This retrospective case–control study included mild/moderate stiffness, severe stiffness, and non-stiffness groups between January 2011 and December 2017 at a single orthopedic center. Multivariable logistic regression analysis and subgroup analysis were used to evaluate age, gender, body mass index, muscle strength, fracture type and site, injury mechanism, immobilization time, elbow dysfunction time, multiple surgeries, nerve symptoms, physical therapy, smoking and alcohol abuse, and dominant hand of stiff elbow as potential risk factors for the occurrence and severity of elbow stiffness.Results: There were 461 patients in the stiffness group and 227 patients in the non-stiffness group. The odds ratios (ORs) of the age, muscle strength, and injury mechanism were 0.960, 0.333, and 0.216 for the occurrence of elbow stiffness. In subgroup evaluation, increased cast immobilization time might be a risk factor for patients receiving conservative therapies (OR = 2.02; p = 0.014). In the evaluation on factors for progression of elbow stiffness, “multiple surgeries” might be a risk factor in surgical treatment by subgroup analysis (OR = 1.943; p = 0.026). Nevertheless, alcohol abuse might increase severity of elbow stiffness in conservatively treated patients (OR = 3.082; p = 0.025).Conclusion: Increased cast immobilization time in the conservative therapy might be a risk factor for stiffness occurrence. Multiple surgeries might be risk factors for stiffness progression. Alcohol abuse potentially increased stiffness severity after conservative treatment.

Orthopedic Injuries in Professional Surfers: A Retrospective Study at a Single Orthopedic Center.

Literature regarding surfing injuries is scarce and most studies report a high number of minor injuries. Recent literature suggests that musculoskeletal injuries are more common than previously reported. In the mid 2000s, competitive surfing has seen an increase in aerial maneuvers, as they have become more highly rewarded by the judging panel, which may be contributing to a change in injury patterns. Our goal was to evaluate orthopedic injuries in professional surfers. Orthopedic injuries in professional surfers are diverse and have evolved with skill and technology. Retrospective observational study. Level 4 Case Series. Medical records of professional surfers from a single orthopedic center between 1991 and 2016 were reviewed. Injuries sustained while surfing and chronic injuries related to surfing were included. Site of injury, diagnosis, and treatment were recorded along with demographic data. In total, 163 injuries in 86 athletes were recorded. The median injury age was 28.5 years (range 12-62 years) and 92.6% of patients were male. The most frequently injured body parts were the knee (28.2%), ankle (22.1%), and shoulder (19%). Most knee injuries were of the medial collateral ligament at 49%, with 75% of ankle injuries being sprains, and in shoulder, 48% had instability, 42% had a rotator cuff tear, and 35% had a superior anterior-posterior labral tear. Lower extremity injuries primarily affected the surfers' back leg (72.5%). In all, 34.6% of all injuries required surgical intervention and involved shoulder injuries most the time. The most common orthopedic injuries in professional surfers involve the knee, ankle, shoulder, hip, and back. Surfers' rear extremities were preferentially injured which is the extremity responsible for power and torque. Shoulder injuries increased the probability of an operative intervention. Last, overuse injuries (femoral-acetabular impingement, rotator cuffs) occurred in the older surf population compared with more acute injuries (ankle sprains/fractures, anterior cruciate ligament tears) which is also consistent with time to surgery.

Observational Study of Depression in Patients Undergoing Cervical Disc Arthroplasty: Evidence of a Correlation between Pain Relief and Resolution of Depression.

Depression has been associated with inferior outcomes following lumbar spine surgery. Our purpose was to investigate the prevalence of depression and its impact on the outcomes of a large sample of cervical disc arthroplasty patients and to examine the change in depression occurring in conjunction with changes in disability and pain. A cohort of 271 patients who underwent single or multi-level cervical disc arthroplasty at a single orthopedic center filled out the Neck Disability Index, Medical Outcomes Study SF-36, numerical rating scales for neck pain and arm pain, preoperatively and 12-month postoperatively. Patients were classified as Depressed or Non-Depressed, based on their preoperative SF-36 Mental Component Summary (MCS) score. Preoperative scores, 12-month postoperative scores, and change in scores (adjusted for preoperative scores, smoking status, and strenuous job) were compared between Depressed and Non-Depressed. Next, patients in the 2 groups were subdivided into 4 groups: Always Depressed, Never Depressed, No Longer Depressed, and Newly Depressed, based on their combined preoperative and postoperative MCS scores. The same score comparisons were conducted among the 4 groups. Forty-four percent (118 of 271) of the patients in our sample were Depressed. Despite a significant improvement after surgery, Depressed patients had poorer pre- and postoperative scores than Non-Depressed patients for NDI, MCS, neck pain and arm pain. Two-thirds (80 of 118) of the Depressed patients were No Longer Depressed at 12 months and had postoperative scores similar to the Never Depressed patients. Eight percent (12 of 153) of the Non-Depressed patients became Newly Depressed by 12 months and had postoperative scores similar to the Always Depressed patients. Depression is a common occurrence in patients with cervical disorders. Relief from pain and disability after cervical disc arthroplasty can be associated with relief from depression, but poor outcomes may also result in patients becoming depressed.

Pyogenic sacroiliitis: diagnosis, management and clinical outcome

The purpose of the present study was to evaluate the role of diagnostic tools and management options for patients with pyogenic sacroiliitis, including potential complications. This retrospective study included 16 patients with pyogenic sacroiliitis who were admitted to a single orthopaedic centre between 2007 and 2012. The following data were collected: demographics, history, radiography, magnetic resonance images (MRI), biological data, type of pathogenic agent, abscess formation, type of management, and clinical outcome. Our study demonstrated that only one-fifth of the patients with lumbogluteal or hip pain had established diagnoses of suspected pyogenic sacroiliitis upon admission. MRIs confirmed this diagnosis in all cases. MRI examinations revealed joint fluid in the sacroiliac joint and significant oedema of the adjacent bone and soft tissues. In 12 of the 16 cases, erosions of the subchondral bone were encountered. Contrast-enhanced MRI revealed that 9 patients had abscesses. All patients received antibiotic therapy. Antibiotic treatment was only successful in 9 cases. The other 7 patients underwent computed tomography (CT)-guided abscess drainage. Drainage was sufficient for 4 patients, but 3 patients required open surgery. One patient required sacroiliac arthrodesis. The clinical outcomes included minimal disability (n = 10), moderate disability (n = 5), and full disability (n = 1) of the spine. Contrast-enhanced MRI is mandatory for a reliable diagnosis. Abscess formation was observed in approximately half of the MRI-diagnosed sacroiliitis cases and required minimally invasive drainage under CT guidance or frequently open surgery.

Characteristics and treatment outcomes of 69 cases with early prosthetic joint infections of the hip and knee

Early prosthetic joint infection (PJI) can be treated with an intensive surgical debridement and implant retention (DAIR) of the prosthesis if (1) the prosthesis is stable, (2) the pathogen is not a difficult-to-treat microorganism, (3) symptoms have lasted for <3 weeks and (4) a sinus tract is absent. We retrospectively evaluated the treatment outcome of early PJI in the hip and knee in a single orthopaedic centre. An early PJI was defined as a prosthesis infection within 3 months after primary implantation or revision surgery for a non-infectious cause. We identified 69 patients with confirmed early PJI, with a median age of 71 (range 33-84) years. Only 64 % presented with ≥2 acute signs of infection. The most commonly isolated bacteria were coagulase-negative staphylococci (38 %) and Staphylococcus aureus (25 %). Surgical procedures included DAIR (50 cases, 69 %) and two-stage exchange (19 cases, 31 %). At last follow-up, five of remaining living 67 patients (7.5 %) had a relapse of infection. The overall relapse-free survival of the prosthesis after 2 years was 92.3 % (95 % confidence interval 82-97 %) with no significant difference between DAIR and exchange of prosthesis. Our data suggest that an early PJI should be treated with DAIR as a less invasive procedure whenever possible according to the established treatment algorithm.

An uncommon cause of cemented unicompartmental knee arthroplasty failure: fracture of metallic components

Despite good overall clinical results, unicompartmental knee replacements (UKR) are not without their problems and failures have been reported. The most common causes of UKR failure are component loosening, poor patient selection, poor surgical technique, polyethylene wear and progression of arthritis in other compartments. The purpose of this study is to present a series of atraumatic fractures of metallic components in a UKR treated in a single orthopaedic centre. Since 1999, 121 failed unicompartmental knee arthroplasties have been referred to our centre. In six of these, atraumatic breakage of a metal component in the cemented UKR was seen and included in this study. Pre-operative alignment, BMI and implant longevity were documented. The femoral implant failed in 4 patients and the tibial implant in a further 2. All the femoral implant fractures occurred within 3 years of UKR surgery (mean: 22.2 months, SD: 10.6 months). Tibial implant breakage occurred at a mean of 8.5 years (SD: 2.4 months) following UKR. All patients were treated with conversion to a navigated total knee replacement. A primary total knee arthroplasty was used in all cases with one patient requiring a tibial component incorporating a wedge and stem following breakage of the original UKR tibial implant. Fracture of the metallic components is a potential cause of failure of unicompartmental knee arthroplasty. In our experience, the incidence of this complication was 4.9 % of all UKR failures. Patients with a BMI greater than 30 and a progressive deterioration in limb alignment were at greater risk.

A comparative study of the medial St Georg Sled and Kinematic total knee arthroplasties

We have studied the long-term outcome of 408 primary medial St George Sled unicompartmental arthroplasties of the knee and 531 primary Kinematic total knee arthroplasties using survivorship analysis. The operations were performed by a number of surgeons under the supervision of two consultants at one orthopaedic centre. Prospective clinical assessment was carried out before and at 2, 5, 8, 10, 12 and 15 years after operation. Failure was defined as follows: revision or removal of the implant; the presence of moderate or severe pain; or ‘worst-case’ with all patients lost to follow-up. Cumulative survival rates at ten years were calculated using life tables. The follow-up rate was 97%. At ten years, 25 medial sled arthroplasties and 20 Kinematic knee arthroplasties had been revised. With revision or removal as the survivorship endpoint at ten years there was a success rate of 87.5% for the medial sled and 89.6% for the Kinematic knee arthroplasty. When moderate or severe pain was included these rates became 79.4% for both arthroplasties. There was no statistically significant (p &gt; 0.05) difference between the rates of survival for the two arthroplasties using either of the endpoint criteria. Good or excellent results were recorded for 77.9% of the medial sled knees and 75.1% for the Kinematic knees. The former had 93.8% of cases with a final range of movement in excess of 90° compared with 83.7% for the Kinematic knees (p &lt; 0.01). We conclude that at a single orthopaedic centre in the UK, the St Georg Sled medial compartment arthroplasty for appropriate specific indications offers predictable survivorship at ten years which is comparable with that of the Kinematic total knee arthroplasty.