Published 2/1/2019

Second Look – Clinical

Hip and knee

Length of TKA surgery and infection—Primary total knee arthroplasty (TKA) patients with longer operative times may be more likely to develop prosthetic joint infections (PJIs) and surgical site infections (SSIs), according to a study published in The Journal of Arthroplasty (online). Researchers evaluated 11,849 primary TKAs performed between Jan. 1, 2014, and Dec. 31, 2017, with a mean two-year follow-up. Procedures exceeding 121 minutes were classified as long cases. Younger patients (mean age, 67 years) and those with a higher body mass index (BMI) (mean, 34 kg/m2) were more likely to have longer cases. Longer cases had a 1.4 percent PJI rate compared to 0.3 percent for cases shorter than 85 minutes. Longer cases also had the highest SSI rate (3.8 percent). Patients whose cases were complicated by PJIs ultimately had longer mean operative times (135 minutes) compared to those who did not develop PJIs (105 minutes); the same trend was observed for SSIs. In adjusted analyses, every 15-minute increase in operative time increased the risk of PJIs and SSIs by 18 percent and 11 percent, respectively.

SSI after ACLR—A study published in Knee Surgery, Sports Traumatology, Arthroscopy (December) found that certain demographic characteristics may predict postoperative SSI risk in patients undergoing anterior cruciate ligament reconstruction (ACLR). Researchers queried the Diagnosis Procedure Combination database and identified 30,536 ACLR patients between 2010 and 2015, of whom 288 (0.94 percent) had an SSI and 86 (0.28 percent) had a deep SSI. Univariate analysis revealed that higher prevalence of SSI and deep SSI was associated with male sex, increased BMI, atopic dermatitis, and preoperative steroid use; SSI was significantly more prevalent in diabetic patients and those with hepatic dysfunction. In multivariable analysis, researchers observed a significant association between SSI and male sex, BMI ≥ 30.0 kg/m2, diabetes, atopic dermatitis, and preoperative steroid use.

Patient satisfaction after TKA—According to a retrospective study published in The Knee (online), TKA patients who are older, have a higher BMI, and do not have hypertension are more likely to be satisfied overall after surgery. However, they may be dissatisfied with their ability to return to recreational activities. Researchers queried an established arthroplasty database to identify 3,324 primary TKA patients. They collected patient demographics, comorbidities, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores, and Short Form (SF)-12 scores preoperatively and one year postoperatively. They assessed overall patient satisfaction and satisfaction with recreational activities after one year. The overall satisfaction rate (89.7 percent) was higher than the satisfaction with recreational activities rate (80.4 percent). One-year components and total WOMAC scores significantly indicated recreational activity satisfaction.

Survival for TKA with cementless tibial tray—A study published in The Journal of Arthroplasty (online) found high survivorship rates and acceptable patient-reported outcomes for mobile bearing TKA with a cementless tibial tray at a minimum 17-year follow-up. Researchers evaluated 500 primary TKAs in 467 patients. The primary endpoint was all-cause revision. After a mean 18.1 years, 141 knees (28.2 percent) were available for review. Cumulative survivorship was 97.4 percent; 13 knees underwent revision: three for deep infection, three bearing-only revisions for spinout, three for tibial tray subsidence, two secondary patella resurfacings, one aseptic loosening, and one for suspected aseptic loosening. Mean American Knee Society scores for evaluation and function were 83 and 48, respectively; mean Oxford Knee Score was 32.1; and mean Bartlett patellar score was 21.6.

TKA conversion after opening wedge HTO—Female sex and older age may be risk factors for conversion to TKA in opening wedge high tibial osteotomy (HTO) patients, according to a study published in The Knee (online). Between 1994 and 2011, 111 opening wedge HTOs (mean patient age, 45 years; 84 percent male) were performed at a single center. Mean follow-up was 12 years. Failure was defined as conversion to TKA. At a mean of 6.3 years, 40 (36.0 percent) HTOs failed. After five, 10, and 15 years, the Kaplan-Meier survival rates were 84 percent, 65 percent, and 55 percent, respectively. Researchers identified age older than 47 years and female sex as independent predictors of failure.

UKA for avascular osteonecrosis of the knee—In a long-term, retrospective study published in The Journal of Arthroplasty (online), patients who underwent unicompartmental knee arthroplasty (UKA) to treat avascular osteonecrosis of the knee (AVN) had high survival rates and stable clinical outcomes. Between 1989 and 2001, two senior surgeons performed 29 consecutive UKAs in 28 patients (19 females; mean age, 67 years; mean BMI, 27 kg/m2) with medial unicompartmental AVN diagnosed by radiography, MRI, and postoperative sample analysis. Etiologies were spontaneous/idiopathic AVN in 19 knees (66 percent) and secondary AVN in 10 knees (33 percent). Mean patient follow-up was 21 years. After 15 years, 92 percent of components survived without any revision. The latest follow-up was 26 years, at which time revision-free survival was 83 percent, mean Knee Society Knee Scoring System (KSS) was 89 points, and functional KSS was 83 points. There was no difference in survivorship between patients with spontaneous or secondary osteonecrosis of the knee.

Outcomes with Birmingham Hip Resurfacing System—In a long-term study published in The Journal of Bone & Joint Surgery (online), patients who underwent surface replacement arthroplasty via the Birmingham Hip Resurfacing (BHR) System had positive clinical outcomes. Researchers collected patient-reported outcomes (PROs) and complication and revision data on 324 hips five years after surface replacement arthroplasty at a single institution. Postoperative modified Harris hip score and University of California, Los Angeles (UCLA) scores greatly improved (to 89.9 and 8.0, respectively). Five and 10 years postoperatively, the Kaplan-Meier estimated rates of survival for all-cause revision were 97.2 percent and 93.8 percent, respectively. Fourteen patients (4.3 percent of all hips) underwent revision. In a matched-cohort analysis, postoperative UCLA scores were significantly better for BHR patients than total hip arthroplasty (THA) patients (8.0 versus 7.6, respectively). High postoperative activity levels were associated with a lower median UCLA score; BHR patients were more likely than THA patients to remain active (61 percent versus 20 percent, respectively).


PROs following lumbar spinal stenosis—A study published in the European Spine Journal (online) measured socioeconomic and clinical factors predictive of PROs in lumbar spinal stenosis (LSS) patients. Data were collected from several registries, including the national quality registry for spine surgery (Swespine). Length of sick leave, global assessment (GA) of leg pain, and the Oswestry Disability Index (ODI) were all evaluated postoperatively. Clinical and socioeconomic factors impacted GA and ODI outcomes. Being born in the European Union, having no baseline back pain, and having high disposable income and education level were all associated with good ODI outcome. Indicators of poor outcome were having prior surgery; having a history of back pain for more than two years; having comorbidities; and being a smoker, on social welfare, or unemployed.

Long-level fusion effects on ADLs—According to a study published in Spine (Dec. 1), long-level fusion in patients with adult spinal deformity (ASD) may impact activities of daily living (ADLs). Patients were stratified into three groups:

  • group 1: patients older than 60 years of age with degenerative spine disease without deformity
  • group 2: ASD patients who did not have surgery
  • group 3: ASD patients who had surgery for deformity correction

Researchers used the Oswestry Low Back Pain Disability Questionnaire and Assessment ADL for sedentary Asian culture (ADL-SA) questionnaire to evaluate outcomes. Group 1 had almost full function in every activity (ADL-SA, 41.4), with similar outcomes observed in group 2. ADL was impaired after long-level fusion, but gradual improvements were observed over time. ADL scores reached an acceptable range one year postoperatively, but sedentary ADL activities remained impaired two years postoperatively.

Outcomes for lumbar degenerative spondylolisthesis—Patients with symptomatic lumbar degenerative spondylolisthesis (DS) who are treated surgically may have better outcomes than those who receive nonsurgical treatment, according to a study published in Spine (Dec. 1). Surgical candidates with DS who had at least 12 weeks of symptoms and whose disease was image-confirmed were enrolled in a randomized, controlled trial or observational cohort study. Researchers compared standard decompressive laminectomy (with or without fusion) to standard nonoperative care. Primary outcome measures were the SF-36 bodily pain and physical function scores and the modified ODI. Outcomes were evaluated at six weeks, three months, six months, and annually for up to eight years. As-treated analyses in both groups showed significantly better outcomes for the surgery group for all primary outcome measures at all time points over the study period. Fusion technique (uninstrumented posterolateral fusion, instrumented posterolateral fusion, and 360-degree fusion) did not impact outcomes.

Surgical considerations

Bariatric surgery and TJA outcomes—A study published in The Journal of Arthroplasty (online) found that bariatric surgery prior to total joint arthroplasty (TJA) in morbidly obese patients may be associated with somewhat better short-term outcomes, but no improvements were observed in long-term outcomes. Researchers queried the EMBASE, PubMed, Web of Science, and Cochrane Library electronic databases for relevant studies published in English. Primary outcome measures were complications and revision; secondary outcome measures were length of stay (LOS) and operative time. Short- and long-term follow-up were defined as time from hospital discharge to 90 days and discharge to one year, respectively. Nine studies with 38,728 patients were included in the final analysis. Prior to TJA, the bariatric surgery group had more overall medical comorbidities than the control group of morbidly obese patients. The incidence of bariatric surgery before TJA was correlated with fewer short-term medical complications and shorter LOS and operative time but not with reduced short-term risks for superficial wound infection or venous thromboembolism. There were no associations with reduced long-term complication risks, including dislocation, periprosthetic infection (PPI), periprosthetic fracture, and revision. In further analysis, patients who underwent bariatric surgery had a reduced risk of short-term PPI after TKA but not after THA.

Postoperative hypothermia—A study published in the Journal of the AAOS (Dec. 15) identified risk factors associated with postoperative hypothermia for orthopaedic surgery patients. Researchers reviewed 3,822 orthopaedic surgical procedures. Hypothermia was considered temperature lower than 36 degrees Celsius. Nearly three-quarters of patients (72.5 percent) experienced intraoperative hypothermia; postoperative hypothermia was observed in 8.3 percent of patients. Intraoperative hypothermia, lower preoperative temperature, female sex, lower BMI, older age, adult reconstruction by specialty, and hip and pelvis procedures by anatomic region were all identified as risk factors for postoperative hypothermia.

The ‘July effect’—A study published in JBJS (online) analyzed the association between complication rates following orthopaedic trauma surgery involving residents and the level of resident training and time of year. Using the American College of Surgeons National Surgical Quality Improvement Program database, researchers identified 1,851 cases of operative fixation of proximal femoral fractures, femoral shaft fractures, and tibial shaft fractures from 2005 to 2012 that involved residents. During the first academic quarter, rates of serious adverse events (AEs) (10.96 percent), any AEs (18.57 percent), and surgical complications (9.62 percent) were similar to those observed for the rest of the year (11.40 percent, 17.81 percent, and 7.19 percent, respectively). During the beginning of the year, senior-level residents were more likely to have AEs (quarter 1, 20.58 percent; quarter 2, 20.05 percent) than junior residents (quarter 1, 11.76 percent; quarter 2, 12.44 percent). The “July effect”—a perceived increase in the risk of medical errors and surgical complications that occurs when U.S. medical school graduates begin residencies—was not observed in lower-extremity orthopaedic surgery, but evidence of this effect was present in superficial SSIs.

Popularity of TDR surgery—According to a study published in International Orthopaedics (online), problems with anterior surgery, imbursement policy, and potential problems with salvage surgery have led to a decrease in total disk replacement (TDR) surgeries. Researchers reviewed 80 studies: 23 literature reviews, 41 studies accepted by “importance criteria” from the internet, and 16 articles published in 2018. Three papers discussed problems associated with state nonimbursement; seven papers discussed salvage surgery, which was considered rare but extremely problematic. According to 16 papers, the anterior approach is a challenging surgery. One paper associated it with a 38.5 percent transient complication rate, another associated it with a 6.6 percent vascular injury rate, one correlated it with a 1.8 percent rate of retrograde ejaculations, and two said an access surgeon was required.

Neck and shoulder

Rotator cuff attrition during treatment for impingement syndrome—A retrospective study published in Archives of Orthopaedic Trauma and Surgery (online) found that spurs protruding from the acromial undersurface did not cause rotator cuff tears during conservative treatment for impingement syndrome. Data were collected for 119 patients with an intact rotator cuff who underwent conservative treatment for a spur protruding from the undersurface of the acromion. Researchers evaluated functional outcomes based on the visual analog scale (VAS) for pain; subjective shoulder value; American Shoulder and Elbow Surgeons score; UCLA shoulder score; and active range of motion (ROM). Cuff integrity was determined through follow-up MRI, CT angiography, or ultrasound at least two years after initial presentation. Follow-up imaging studies did not identify any new rotator cuff tears, but 18 patients (15 percent) required arthroscopic acromioplasty. Arthroscopic examinations revealed moderate to severe cuff attrition. Pain level, shoulder function, and ROM all improved at final follow-up.

Sleeping positions that reduce glenohumeral pain—Certain sleep postures may be associated with decreased glenohumeral shoulder pain and rotator cuff tendinopathy (RCT), according to a cross-sectional analysis published in BMC Musculoskeletal Disorders (online). The study included 761 workers (average age, 41 years; 68.9 percent female) who reported glenohumeral shoulder pain within the previous 30 days. The workers identified their primary and secondary preferred sleeping positions from a choice of six diagrams. They also underwent a structured physical examination to determine the presence of RCT. Researchers hypothesized that overhead sleep postures and sleeping on the side would increase glenohumeral shoulder pain and RCT, but no association was found. The two sleep postures that researchers predicted would cause pain—“freefaller” and “starfish”—were actually found to be more protective.

Foot and ankle

Driving after ankle fracture surgery—A study published in the Archives of Orthopaedic and Trauma Surgery (December) found that patients who undergo surgery to treat a right ankle fracture may be able to pass a standard driving test as soon as six weeks postoperatively, even before initiating weight bearing. Researchers included patients aged 23–65 years who had right ankle fracture surgery and a valid driver’s license. Patients were evaluated at two, six, and 12 weeks postoperatively; they completed a Short Musculoskeletal Function Assessment (SMFA) questionnaire, and a driving simulator measured their brake reaction time. Eligible patients then took an on-road driving test with an instructor and were surveyed after six months to see whether they had returned to driving safely. Final analyses included 23 patients (mean age, 42.8 years). At six and 12 weeks postoperatively, SMFA and braking time significantly improved. Most patients (91 percent) passed the six-week on-road driving test before the fracture was healed or weight bearing was initiated. At six-month follow-up, all patients were safely driving again.

Complications after repair of Achilles tendon rupture—Patients undergoing treatment for acute Achilles tendon rupture may face fewer complications with minimally invasive treatment compared to open surgical repair, according to a literature review published in JBJS (online). Eligible studies were randomized, controlled trials that compared minimally invasive surgery and open repair of acute Achilles tendon ruptures. In the eight studies reviewed, 182 patients were treated with minimally invasive surgery and 176 with open repair. The risk of overall complications and wound infection was lower in patients who received minimally invasive surgery compared to those who underwent open surgery, and patients who had minimally invasive surgery were more likely to report positive subjective results. Rates of re-rupture, sural nerve injury, return to preinjury activity level, time to return to work, and ankle ROM did not differ largely between the groups.

Wrist and hand

Opioid use after hand surgery—Patients may find similar postoperative pain relief with ibuprofen or hydrocodone in combination with acetaminophen after elective, soft-tissue hand surgery, according to a study published in The Journal of Hand Surgery (online). Researchers randomized 60 patients to receive acetaminophen/hydrocodone 325/5 mg (AH, n = 30) or acetaminophen/ibuprofen 500/400 mg (AIBU, n = 30). Patients were followed for two weeks postoperatively and evaluated for daily pain intensity based on VAS score, medication pain relief (Likert pain relief score), need for rescue opioid prescription at one week, and days until pain-free. Both groups had a similar mean VAS scores and number of days until pain-free (AH group, five days; AIBU group, three days). In both groups, two patients needed rescue opioid medication. The AIBU group had greater pain relief, but the difference was not significant. The AH group had a higher rate of side effects (23 percent) than the AIBU group (3 percent), but none of the side effects was severe.


Lisfranc joint radiographic measurements—In a retrospective review published in the Journal of Pediatric Orthopaedics (November/December), researchers found that the distance between the base of metatarsal 1 and metatarsal 2 (MT1–MT2) and the distance between the medial cuneiform (MC) and the base of metatarsal 2 (MC–MT2) in children approached adult values at six years of age. Final analysis included 243 patients younger than 18 years of age who underwent foot radiographs without traumatic injury at a single institution between August 2014 and February 2015. Patients were excluded if they had an anatomic abnormality; fracture; inadequate radiograph; pain at the base of the MT1, MT2, or MC; persisting pain at the outpatient clinic checkup; or no follow-up. Researchers observed a constant measurement between the base of the MT1–MT2 shorter than 3 mm.