Deep learning of renal scans in children with antenatal hydronephrosis

INTRODUCTION

Antenatal hydronephrosis (ANH) is one of the most common anomalies identified on prenatal ultrasound, found in up to 4.5% of all pregnancies. Children with ANH are surveilled with repeated renal ultrasound and when there is high suspicion for a ureteropelvic junction obstruction on renal ultrasound, a mercaptuacetyltriglycerine (MAG3) Lasix renal scan is performed to evaluate for obstruction. However, the challenging interpretation of MAG3 renal scans places patients at risk of misdiagnosis.

OBJECTIVE

Our objective was to analyze MAG3 renal scans using machine learning to predict renal complications. We hypothesized that our deep learning model would extract features from MAG3 renal scans that can predict renal complications in children with ANH.

STUDY DESIGN

We performed a case-control study of MAG3 studies drawn from a population of children with ANH concerning for ureteropelvic junction obstruction evaluated at our institution from January 2009 until June of 2021. The outcome was renal complications that occur ≥6 months after an equivocal MAG-3 renal scan. We created two machine learning models: a deep learning model using the radiotracer concentration versus time data from the kidney of interest and a random forest model created using clinical data. The performance of the models was assessed using measures of diagnostic accuracy.

RESULTS

We identified 152 eligible patients with available images of which 62 were cases and 90 were controls. The deep learning model predicted future renal complications with an overall accuracy of 73% (95% confidence inteveral [CI] 68-76%) and an AUC of 0.78 (95% CI 0.7, 0.84). The random forest model had an accuracy of 62% (95% CI 60-66%) and an AUC of 0.67 (95% CI. 0 64, 0.72) DISCUSSION: Our deep learning model predicted patients at high risk of developing renal complications following an equivocal renal scan and discriminate those at low risk with moderately high accuracy (73%). The deep learning model outperformed the clinical model built from clinical features classically used by urologists for surgical decision making.

CONCLUSION

Our models have the potential to influence clinical decision making by providing supplemental analytical data from MAG3 scans that would not otherwise be available to urologists. Future multi-institutional retrospective and prospective trials are needed to validate our model.

Automated Society of Fetal Urology (SFU) grading of hydronephrosis on ultrasound imaging using a convolutional neural network

INTRODUCTION

Grading of hydronephrosis severity on postnatal renal ultrasound guides management decisions in antenatal hydronephrosis (ANH). Multiple systems exist to help standardize hydronephrosis grading, yet poor inter-observer reliability persists. Machine learning methods may provide tools to improve the efficiency and accuracy of hydronephrosis grading.

OBJECTIVE

To develop an automated convolutional neural network (CNN) model to classify hydronephrosis on renal ultrasound imaging according to the Society of Fetal Urology (SFU) system as potential clinical adjunct.

STUDY DESIGN

A cross-sectional, single-institution cohort of postnatal renal ultrasounds with radiologist SFU grading from pediatric patients with and without hydronephrosis of stable severity was obtained. Imaging labels were used to automatedly select sagittal and transverse grey-scale renal images from all available studies from each patient. A VGG16 pre-trained ImageNet CNN model analyzed these preprocessed images. Three-fold stratified cross-validation was used to build and evaluate the model that was used to classify renal ultrasounds on a per patient basis into five classes based on the SFU system (normal, SFU I, SFU II, SFU III, or SFU IV). These predictions were compared to radiologist grading. Confusion matrices evaluated model performance. Gradient class activation mapping demonstrated imaging features driving model predictions.

RESULTS

We identified 710 patients with 4659 postnatal renal ultrasound series. Per radiologist grading, 183 were normal, 157 were SFU I, 132 were SFU II, 100 were SFU III, and 138 were SFU IV. The machine learning model predicted hydronephrosis grade with 82.0% (95% CI: 75-83%) overall accuracy and classified 97.6% (95% CI: 95-98%) of the patients correctly or within one grade of the radiologist grade. The model classified 92.3% (95% CI: 86-95%) normal, 73.2% (95% CI: 69-76%) SFU I, 73.5% (95% CI: 67-75%) SFU II, 79.0% (95% CI: 73-82%) SFU III, and 88.4% (95% CI: 85-92%) SFU IV patients accurately. Gradient class activation mapping demonstrated that the ultrasound appearance of the renal collecting system drove the model's predictions.

DISCUSSION

The CNN-based model classified hydronephrosis on renal ultrasounds automatically and accurately based on the expected imaging features in the SFU system. Compared to prior studies, the model functioned more automatically with greater accuracy. Limitations include the retrospective, relatively small cohort, and averaging across multiple imaging studies per patient.

CONCLUSIONS

An automated CNN-based system classified hydronephrosis on renal ultrasounds according to the SFU system with promising accuracy based on appropriate imaging features. These findings suggest a possible adjunctive role for machine learning systems in the grading of ANH.

Early urodynamic findings after complete primary repair of exstrophy

INTRODUCTION

Detrusor contraction in bladder exstrophy (BE) patients following reconstruction is poorly understood as there are few published studies assessing urodynamic findings in this population. Understanding the ability of the detrusor to contract in BE patients early after closure may be able to inform the longer-term management and potential for the development of future continence in this population.

OBJECTIVE

We sought to evaluate early detrusor contraction using urodynamic studies (UDS) in children who had previously undergone complete primary repair of bladder exstrophy (CPRE). We hypothesized that a majority of children with BE would display the presence of normal detrusor contractile function after CPRE.

STUDY DESIGN

A retrospective review of our prospectively collected database was performed for all patients with a diagnosis of classic BE who underwent primary CPRE between 2013 and 2017. From this cohort we identified patients with at least one post-operative UDS at 3 years of age or older who had undergone an initial CPRE. Our primary outcome was the presence of a detrusor contraction demonstrated on UDS.

RESULTS

There were 50 children (31 male, 19 female) with CBE who underwent CPRE between 2013 and 2017.There were 26 (13 male, 13 female) who met inclusion criteria. Median age was 3.5 (IQR: 3.2-4.7) years at the time of UDS Sixteen of the 26 (61.5%) generated a sustained detrusor contraction generating a void, with a median peak voiding pressure of 38 cm H20 (IQR: 28-51). The median bladder capacity reached was 48 ml, which represented a median of 30% of expected bladder capacity. The median post void residual (PVR) for the entire cohort was 26 ml (IQR: 9, 47) or 51% (IQR: 20%-98%) of their actual bladder capacity, while the median PVR for those children with a sustained detrusor contraction was 18 ml (IQR: 5, 46) or 33% (IQR: 27%, 98%) of their actual bladder capacity. Intraoperative bladder width and bladder dome to bladder neck length did not correlate with the presence of voiding via a detrusor contraction (p = 0.64).

DISCUSSION

We present the first study assessing early UDS finding of detrusor contraction in BE patients after CPRE. In our cohort, 61.5% of patients were able to generate a sustained detrusor contraction on UDS which is a higher percentage than has been reported in previous series. A difference in initial surgical management may account for these findings.

CONCLUSION

At short term follow up, the majority of children in our cohort were able to produce sustained detrusor contractions sufficient to generate a void per urethra with a modest post void residual volume. Long-term follow-up and repeated UDS will be needed to track detrusor contractility rates, bladder capacities, compliance, post void residuals and ultimately continence rates over time.

Deep Learning of Videourodynamics to Classify Bladder Dysfunction Severity in Patients With Spina Bifida

PURPOSE

Urologists rely heavily on videourodynamics to identify patients with neurogenic bladders who are at risk of upper tract injury, but their interpretation has high interobserver variability. Our objective was to develop deep learning models of videourodynamics studies to categorize severity of bladder dysfunction.

MATERIALS AND METHODS

We performed a cross-sectional study of patients aged 2 months to 28 years with spina bifida who underwent videourodynamics at a single institution between 2019 and 2021. The outcome was degree of bladder dysfunction, defined as none/mild, moderate, and severe, defined by a panel of 5 expert reviewers. Reviewers considered factors that increase the risk of upper tract injury, such as poor compliance, elevated detrusor leak point pressure, and detrusor sphincter dyssynergia, in determining bladder dysfunction severity. We built 4 models to predict severity of bladder dysfunction: (1) a random forest clinical model using prospectively collected clinical data from videourodynamics studies, (2) a deep learning convolutional neural network of raw data from the volume-pressure recordings, (3) a deep learning imaging model of fluoroscopic images, (4) an ensemble model averaging the risk probabilities of the volume-pressure and fluoroscopic models.

RESULTS

Among 306 videourodynamics studies, the accuracy and weighted kappa of the ensemble model classification of bladder dysfunction when at least 75% expected bladder capacity was reached were 70% (95% CI 66%,76%) and 0.54 (moderate agreement), respectively. The performance of the clinical model built from data extracted by pediatric urologists was the poorest with an accuracy of 61% (55%, 66%) and a weighted kappa of 0.37.

CONCLUSIONS

Our models built from urodynamic pressure-volume tracings and fluoroscopic images were able to automatically classify bladder dysfunction with moderately high accuracy.

Deep learning imaging features derived from kidney ultrasounds predict chronic kidney disease progression in children with posterior urethral valves

BACKGROUND

We sought to use deep learning to extract anatomic features from postnatal kidney ultrasounds and evaluate their performance in predicting the risk and timing of chronic kidney disease (CKD) progression for boys with posterior urethral valves (PUV). We hypothesized that these features would predict CKD progression better than clinical characteristics such as nadir creatinine alone.

METHODS

We performed a retrospective cohort study of boys with PUV treated at two pediatric health systems from 1990 to 2021. Features of kidneys were extracted from initial postnatal kidney ultrasound images using a deep learning model. Three time-to-event prediction models were built using random survival forests. The Imaging Model included deep learning imaging features, the Clinical Model included clinical data, and the Ensemble Model combined imaging features and clinical data. Separate models were built to include time-dependent clinical data that were available at 6 months, 1 year, 3 years, and 5 years.

RESULTS

Two-hundred and twenty-five patients were included in the analysis. All models performed well with C-indices of 0.7 or greater. The Clinical Model outperformed the Imaging Model at all time points with nadir creatinine driving the performance of the Clinical Model. Combining the 6-month Imaging Model (C-index 0.7; 95% confidence interval [CI] 0.6, 0.79) with the 6-month Clinical Model (C-index 0.79; 95% CI 0.71, 0.86) resulted in a 6-month Ensemble Model that performed better (C-index 0.82; 95% CI 0.77, 0.88) than either model alone.

CONCLUSIONS

Deep learning imaging features extracted from initial postnatal kidney ultrasounds may improve early prediction of CKD progression among children with PUV. A higher resolution version of the Graphical abstract is available as Supplementary information.

Bilateral ureteral reimplantation at complete primary repair of exstrophy: Post-operative outcomes

BACKGROUND AND STUDY OBJECTIVE

The value of bilateral ureteral reimplant (BUR) at the time of complete primary repair of bladder exstrophy (CPRE) has been suggested, however, outcomes are poorly characterized in current medical literature. We hypothesize that BUR at time of CPRE will decrease the rate of recurrent pyelonephritis, post-operative vesicoureteral reflux (VUR), and the need for subsequent ureteral surgery.

STUDY DESIGN

We analyzed 64 consecutive patients with a diagnosis of classic bladder exstrophy (BE) who underwent CPRE at three institutions from 2013 to 2019.15 patients underwent cephalotrigonal BUR-CPRE and 49 patients underwent CPRE alone. Our primary outcome was >1 episode of pyelonephritis as documented in the medical record. Secondary outcomes were persistent vesicoureteral reflux (VUR), with a sub-analysis of number of refluxing renal units and presence of dilating VUR, and the need for subsequent ureteral surgery. Descriptive statistics in addition to standard, two tailed univariate statistics, were used to compare the groups where appropriate.

RESULTS

BUR-CPRE was associated with a significant decrease in the rates of post-operative VUR, number of refluxing renal units, and need for subsequent ureteral surgery (p = 0.002, p = 0.001, and p = 0.048 respectively). There was a reduction in the rates of recurrent pyelonephritis and dilating reflux in patients undergoing BUR-CPRE, though it did not reach significance. Female gender was significantly associated with recurrent pyelonephritis regardless of BUR-CPRE status (p = 0.005). There were no reports of distal ureteral obstruction or other complications following BUR-CPRE. The mean post-operative follow up for the BUR-CPRE group was 46.33 (10.26) months vs. 53.76 (26.05) months for CPRE (p = 0.11).

DISCUSSION

Recurrent pyelonephritis following bladder closure in patients with BE is a well-documented surgical complication, with centers performing CPRE reporting rates of post-operative pyelonephritis from 22 to 50%. Our series demonstrates similar efficacy of BUR-CPRE compared to other contemporary series and provides additional detail about need for subsequent ureteral surgeries and increased long term follow-up of these complex patients. Limitations of the study include male predominance of the cohort and lack of randomization of BUR-CPRE.

CONCLUSIONS

BUR-CPRE decreases postoperative VUR and the need for additional ureteral surgery in select BE patients; it should be considered when technically feasible. While results continue to suggest a trend toward decreased recurrent pyelonephritis and dilating reflux, further longitudinal follow-up in our cohort will be needed.

Clinical outcomes after increasing bladder outlet resistance without augmentation cystoplasty in neurogenic bladder

INTRODUCTION

Patients with neurogenic bladder (NGB) and urinary incontinence (UI) due to low bladder outlet resistance may require bladder neck procedures (BNPs) to achieve continence. These patients may also have reduced bladder capacity and or elevated detrusor storage pressures that require augmentation cystoplasty (AC). AC is not without complications that include risks for bladder rupture, urolithiasis, urinary tract infections and metabolic issues. Avoidance of AC would be helpful in patients with neurogenic urinary incontinence that have safe bladder parameters in the setting of low bladder outlet resistance.

OBJECTIVE

To determine if pre-operative urodynamics could select children with NGBs and UI for isolated BNPs without AC. Additionally we sought to determine the safety of BNPs without AC and future need of AC with long-term follow-up.

STUDY DESIGN

This is an IRB-approved retrospective analysis of all patients undergoing BNPs for management of neurogenic UI over a 17-year period. We separated these BNP patients into two groups: No AC + BNP (Group 1) vs. AC + BNP (Group 2). Our primary analyses focused on postoperative outcomes for patients in Group 1. Outcomes assessed included additional surgical procedures, urodynamic changes, development of CKD, new hydronephrosis (HDN) and vesicoureteral reflux (VUR). Secondary analysis included the timeline for the development of any bladder deterioration that necessitated AC in Group 1.

RESULTS

93 patients underwent BNP at a mean age of 10.8 years. Thirty did not have AC at the time of surgery (Group 1). These children had larger (p < 0.001) and more compliant (p < 0.001) bladders than Group 2 having simultaneous augmentation. At 6 years mean follow-up in Group 1 patients, three developed new reflux and three had new hydronephrosis. Nine (30%) had additional continence procedures. Twelve required (40%) AC at a mean of 23 months after the initial BNP. No patients had AC after 5 years. Detrusor end filling pressure increased 14.8 cm H2O (p = 0.028) and expected bladder capacity decreased 26.1% (p = 0.005) after isolated BNP.

DISCUSSION

We found that from our cohort of patients who had normal bladder compliance and normal/near normal expected capacity preoperatively 40% required subsequent AC. We were unable to find pre-operative clinical parameters which predicted failure or conversion to AC. We found that 43.3% of our BNP without AC patients had no subsequent invasive procedures with mean 6-year follow-up. We found that none of our patients developed any degree of CKD. Finally, we found that the majority of patients that converted to AC after their BNP did so within the first 2 years after their initial BNP and no patients required augmentation 5 years post their initial BNP. This data validates that these patients require very strict follow up, particularly in the first 5 years after surgery.

CONCLUSIONS

BNP without AC is safe in only a few selected patients with NGB. Despite preoperative selection, there are significant changes in bladder dynamics and 40% required subsequent augmentation. Bladder deterioration occurs early and generally in the first 2 years. Since there are no apparent reliable pre-operative variables predicting the need for subsequent AC, parents should be counseled regarding vigilant post-operative follow-up.

Prostate Magnetic Resonance Imaging Provides Limited Incremental Value Over the Memorial Sloan Kettering Cancer Center Preradical Prostatectomy Nomogram

OBJECTIVE

To examine the incremental value of prostate magnetic resonance imaging (MRI) when used in combination with the currently available preoperative risk stratification tool, the Memorial Sloan Kettering Cancer Center (MSKCC) preradical prostatectomy nomogram.

MATERIALS AND METHODS

We reviewed our institutional database of prostate MRI performed before radical prostatectomy between December 2014 and March 2016 (n = 236). We generated a logistic regression model based on observed final pathology results and the MSKCC nomogram predictions for organ-confined disease, extracapsular extension (ECE), seminal vesicle invasion, and lymph node involvement (LNI) ("MSKCC only"). We then generated a combined regression model incorporating both the MSKCC nomogram prediction with the degree of prostate MRI suspicion ("MSKCC + MRI"). Receiver operating characteristic curves were generated, and the area under the curves (AUCs) were compared.

RESULTS

When independently examining the MSKCC nomogram predicted risk and the degree of prostate MRI suspicion, MRI was a predictor for ECE (odds ratio 2.8, P <.01) and LNI (odds ratio 5.6, P = .01). When examining the "MSKCC + MRI" and "MSKCC only" models, the incremental benefit in risk discrimination from the combined model ("MSKCC + MRI") was not significant for organ-confined disease, ECE, seminal vesicle invasion, or LNI (ΔAUC +0.03, P = .10; ΔAUC +0.03, P = .08; ΔAUC 0.63, P = .63; ΔAUC +0.04, P = .42; respectively).

CONCLUSION

A combined model with prostate MRI and the MSKCC nomogram provides no additional risk discrimination over the MSKCC nomogram-based model alone. Evaluation of prostate MRI as a predictive tool should be performed in combination with, not independent of, these clinical risk stratification models.

Presence of Magnetic Resonance Imaging Suspicious Lesion Predicts Gleason 7 or Greater Prostate Cancer in Biopsy-Naive Patients

OBJECTIVE

To compare the relative value of magnetic resonance imaging (MRI) in biopsy-naive patients to those with previous negative biopsy. Although MRI-targeted biopsy has been studied in several major prostate cancer (PCa) cohorts (biopsy naive, previous negative biopsy, and active surveillance), the relative benefit in these cohorts has not been established.

METHODS

We retrospectively reviewed biopsy-naive (n = 45) and previous negative biopsy (n = 55) patients who underwent prostate MRI prior to biopsy at our institution. Patients with an MRI suspicious region (MSR) underwent MRI-targeted biopsy as well as a systematic template biopsy, whereas those without MSR underwent only the template biopsy. All biopsies were performed with the TargetScan (Envisioneering, Pittsburgh, PA) biopsy system. MRI targeting was performed with cognitive guidance.

RESULTS

On multivariate logistic regression, the presence of an MSR was the only statistically significant and independent predictor of Gleason ≥ 7 PCa on biopsy for biopsy-naive men (odds ratio [OR] 40.2, P = .01). For men with previous negative biopsy, the presence of MSR was not a predictor of Gleason ≥ 7 PCa on biopsy (OR 4.35, P = .16), whereas PSA density > 0.15 ng/mL(2) was a significant and independent predictor (OR 66.2, P < .01).

CONCLUSION

Prostate MRI should be considered prior to biopsy in all patients presenting with clinical suspicion for PCa, as presence of a MSR will help guide prebiopsy counseling and provide an opportunity for MRI targeting during biopsy.

Office carpal tunnel release with wrist block and wrist tourniquet

Carpal tunnel release is usually performed in a hospital setting with regional anesthesia. The cost for use of the hospital operating room, anesthesia, and surgeon's fee is quite excessive. Over the past 5 years we have performed carpal tunnel releases in the office setting using wrist block anesthesia and a wrist tourniquet. There have been no complications, and the 20 patients interviewed and examined for this article preferred the office procedure over the hospital procedure. Carpal tunnel release can be performed safely in the office, and is less expensive than when done in a hospital setting.

Don't forget the Bristow-Latarjet procedure

The authors have been disturbed by a number of reports appearing in the past 5 years condemning the Bristow procedure because of difficulties with screw failure and misplacement, nerve damage, and tethering of the subscapularis. A retrospective study was performed comparing the Bankart and Bristow procedures as performed by the authors during a 10-year period. Complications, rate of recurrence, presence of subluxation, range of motion, return to activity, strength, pain, and overall satisfaction were evaluated. There were 85 patients in the study, of which 61 had the Bristow operation and 24 were treated with the Bankart procedure. The minimum followup was 2 years. Very little difference was found between the 2 operations in any of the parameters studied, and in the authors' opinion, the Bristow procedure remains a reasonable alternative to the Bankart operation. The range of abduction, external rotation, and strength compared favorably with the Bankart group. The authors have encountered instances wherein capsular deficiency rendered the accomplishment of the Bankart procedure difficult or unreliable. Four such cases are reported. Under these circumstances, the Bristow served as a reliable alternative. Technical recommendations for avoiding the difficulties that have led to the condemnation of the Bristow procedure are described in detail.

Difficulties with bearing dislocation and breakage using a movable bearing total knee replacement system

In 1980, the low contact stress, or New Jersey, system was introduced with movable high-density polyethylene bearings between the metallic femoral and tibial components. This system was developed to deal with two principal concerns of conventional knee replacement systems: loosening and wear. A federal Drug Administration review was required, and the study was performed in two phases. From 1981 until 1984, components were cemented in 40 knees, which then were evaluated for an average of seven years after surgery. From 1984 until 1986, 16 knees were selected for cementless fixation and were followed for an average of five years. The cemented group had a failure rate of 10% (four knees), two from tibial component loosening, one from bearing dislocation, and one from infection. Failure was determined by the necessity for revision. The uncemented group had a failure rate of 31% (four knees from bearing fracture and one from knee pain of uncertain source). Bearing failure was attributable to the entrapment of the subluxed lateral bearing. Sacrifice of the anterior cruciate ligament predisposes the system to bearing subluxation and failure.

Ankle pain following total knee arthroplasty. A case report

The authors present their experience with four cases of ankle pain occurring in the immediate postoperative period after total knee arthroplasty. In a 40-month period, the authors performed 87 total knee arthroplasties. In the first 28 cases, an extramedullary alignment rod was used and there were no instances of ankle pain (0%). In the next 30 cases, an intramedullary alignment rod was employed and there were three cases of moderate to severe ankle pain (10%). In the last 29 cases, the medullary canal was decompressed, irrigated, and aspirated prior to insertion of the alignment rod. In this group there was only one case of mild ankle discomfort (3.5%). An extensive investigation was made into one of the cases in which the intramedullary alignment rod was used but the canal was not aspirated. Information from this case investigation, observation of the three subsequent cases, and the notation of a decrease in the incidence of ankle pain once aspiration was routinely used are reported. The unproven hypothesis that ankle pain may result from compression of the marrow contents into the bone interstices is presented for consideration. Three of the four cases of ankle pain reported here were spontaneously resolved within 9 months after surgery.

Patellofemoral arthritis resulting from malalignment. A long-term evaluation of treatment options

This study examines and compares three treatment options for patellofemoral arthritis resulting from patellofemoral malalignment: longitudinal semipatellectomy, total patellectomy, and a modified Trillat procedure. Patients returned for examination in a 3- to 12-year follow-up period. Results from longitudinal semipatellectomy were unsatisfactory, with a reoperation and failure rate of 70%. Good long-term effects were found with total patellectomy (87% good or excellent). The modified Trillat procedure was effective in preventing recurrent dislocation (94%); however, the procedure was less effective in relieving anterior knee pain (65% good or excellent). A satisfactory solution remains to be found.

Treatment of comminuted distal radial fractures with preliminary horizontal finger trap traction and a Roger-Anderson external fixation device

Over a five-year period, 43 patients with comminuted distal radial fractures were treated with a Roger-Anderson external fixation device after the fracture was aligned in Strong's horizontal finger trap traction. Nineteen patients (21 wrists) were available for personal interview and radiographic follow-up. A 0.5-mm loss of radial height and an average loss of 2.4 degrees of palmar angulation presented. Range of motion (ROM) was excellent, stiffness was nonexistent or minimal in 81%, pain was nonexistent or minimal in 86%, and weakness of grasp was nonexistent or minimal in 81%. Complications were minimal; they included three pin tract infections, two of which required pin removal before they resolved. One patient fractured a pin that also required removal. Strong's horizontal finger trap traction and the Roger-Anderson external fixation device simplified the sometimes difficult treatment of this fracture. It seems to be most effective in young athletic individuals who have good bone stock and very comminuted fractures.

Changing patterns in tibial fractures resulting from skiing

Of the 734 adult tibial fractures treated in Aspen, Colorado, from 1968-1978, follow-up results were obtained on 527 (72%). The fractures were analyzed with regard to rate of healing, age of patient, and location of fractures. There was a statistically significant increase in healing time with increasing age between ages 16-40. The location of tibial fracture (proximal, middle, distal) had no significant influence on rate of healing. The occurrence of open tibial fracture was low (3% of total) and in most instances wounds were benign (Class I). Compartment syndrome is rarely encountered in skiing fracture because of the relatively low energy involved. All tibial fractures occurring between 1982-1984 were reviewed and compared to the earlier series. This comparison confirmed the continual overall decline in rate of tibial fracture from skiing (from 12.9/100,000 skier days in 1968 to 2.9/100,000 skier days in 1983). This decline was primarily in spiral fractures (from 70% of total in 1968 to 50% in 1983). The percent of transverse fractures was unchanged (+/- 15%) while the percent of short oblique fractures increased from 11% to 33%. Properly adjusted and maintained safety equipment afforded reasonable protection from spiral fractures of the tibia, but a conceptual departure from the current release binding design would be required to protect against the benign moments that produced transverse and short oblique fracture. The current treatment philosophy is based on fracture type and the availability or experience with newer treatment modes.

Skiing-related injuries to the shoulder

An analysis of 135 consecutive shoulder injuries seen in one clinic during a single ski season revealed anterior dislocation to be the most common ailment, constituting 52% of the total. Rotator cuff tears accounted for 20% of the total, followed by acromioclavicular (AC) separations (18%) and a miscellaneous group of contusions and isolated fractures comprising the other 10%. All of the shoulder dislocations were anterior, most were primary (81%) and men (83%) were involved more frequently. Twenty-four percent of the dislocations were thought to be equipment related. At follow-up examination three to four years after injury, a significant number (41%) were still symptomatic either from a recurrence (18%) or pain and weakness (23%). Patients with rotator cuff tears tended to be about ten years older than the average skier. Their injuries were usually a result of a fall on ipsilateral arm and were not equipment related. Of the 13 patients responding after a three-year follow-up period, most (10/13) were asymptomatic. There were 24 AC separations. All resulted from a direct fall on the shoulder. Sixty percent were first degree, 22% were second degree, and 18% were third degree. About one-third of the respondents with first and second degree injuries were still having significant pain at three-year follow-up examination. The most frequent isolated fracture was a minimally displaced fracture of the greater tuberosity (only three cases in 135 injuries), but this same fracture occurred in 10% of the shoulder dislocations.

Acute surgical repair of the skier's thumb

Complete ulnar collateral ligament tears incurred during the period fall 1977 through spring 1979 were treated under regional anesthesia by a single group of surgeons in an identical fashion as outpatients. Of 123 thumbs repaired, 69 (59%) were available for follow-up examination. There were 34 women and 35 men with an average age of 34.5 years (range, 16-61 years). The follow-up period averaged 31.6 months (range, 16-46 months). Weakness of pinch was described as none or mild in 66 (96%) and significant in only three (4%). Stiffness was described as none or mild in 66 (96%), moderate in two (3%), and severe in one (1%). Pain was described as none or mild in 68 (99%) and moderate in one (1%). Sixty-two patients (90%) preferred outpatient surgery with regional anesthesia whereas only seven (10%) did not. Forty-five (65%) of the 69 patients who required surgery had used traditional poles with straps, suggesting the pole as the causative factor. However, only 20% of noninjured skiers during the 1981-1982 season were using traditional poles with straps, and the total number of complete ulnar collateral ligament repairs did not decrease with the same number of skiers. Therefore, the change in pole design has not decreased the incidence of total ulnar collateral ligament tears. The results of acute surgical repair as an outpatient with regional anesthesia are excellent; 96% of the patients were pleased with the results. If the lesion is overlooked, the results of secondary construction are not nearly as good.

Primary knee ligament repair--revisited

There were 4710 knee sprains resulting from skiing in the four Aspen ski areas between 1976 and 1979. Twenty percent of the patients (942) had complete tears. Of these, 302 elected to remain in Aspen for treatment. All were treated by primary ligament repair without augmentation. These cases were evaluated an average of 42 months after injury. Patients with isolated tears of the medial collateral ligament were found to be doing well; virtually all of them had returned to preinjury activity levels. Thirty-six percent of the isolated anterior cruciate repairs were rated failures, and 43% of the combination ACL-MCL injuries had failed because of anterior cruciate deficiency. Twenty-nine percent of the ACL and ACL-MCL injuries had meniscal tears. Cases that included meniscectomy had a failure rate twice as great as those in which the meniscus was preserved. The results following repair of anterior cruciate tears were not acceptable, and augmentation was indicated. Primary repair of medial collateral ligament tears produced excellent results. Meniscal tears were frequent in association with ligament disruption. Ligament repairs were less satisfactory when meniscectomy was performed at the time of the repair.

A systematic approach to the surgical treatment of chronic shoulder pain

A systematic surgical approach for dealing with chronic shoulder pain includes a carefully designed arthrectomy of the acromioclavicular joint, removal of the coracoacromial ligament, cuff repair, biceps tendon transfer, and removal of calcific deposits as indicated. Of 38 patients who have been followed for at least 24 months, 29 were rated as excellent on the basis of achieving a full range of pain-free movement and normal strength. Degenerative arthritis of the acromioclavicular joint was found in all cases, whereas bicipital tendinitis was noted in less than half. Inspection or transfer of the biceps tendon is not thought to be necessary, because adequate decompression will relieve bicipital tendinitis. An additional reward produced by resection of the lateral 1 ½ cm of the clavicle and the acromial portions of the AC joint is an excellent exposure of the lesional portion of the shoulder for performing cuff repairs, biceps tendon transfers, or excision of calcific deposits. A properly designed removal of the acromioclavicular joint provides adequate anterior decompression and eliminates the most commonly diseased tissue in the chronically painful shoulder without compromising function.

Total hip replacement: a comparison between the transtrochanteric and posterior surgical approaches

It can be argued with good justification, that the trochanteric complications which stimulated this study could have been avoided by strict adherence to Charnley's technique regarding trochanteric advancement and re-attachment. Should trochanteric reattachment be required, it should be done with strict attention to the details outlined by Charnley, or by use of some other device such as the Volz bolt. Trochanteric removal is usually unnecessary. The transtrochanteric approach to total hip replacement has inherent technical problems that increase the potential for complications. These problems include: painful trochanteric bursitis, displacement of trochanter, non-union of trochanter, broken wires and, an increase in dislocation rate (12% as compared to 4%). The posterior approach reduces operative time, blood loss, hospitalization, and shortens the period of time to unprotected weight bearing. Should certain conditions such as external rotation contracture, acetabular protrusion, or relative lengthening of the operated limb indicate trochanteric osteotomy, it can be accomplished readily by way of the posterior exposure.