Bone channeling in arthroscopic rotator cuff repair: a systematic review and meta-analysis of level I studies

BACKGROUND

There is ongoing controversy regarding the effect of bone channeling in arthroscopic rotator cuff repair. Since the most recent systematic reviews in 2019, several large high-level trials have been completed. This study assessed all available level I randomized controlled trials (RCTs) that compared arthroscopic rotator cuff repair with and without bone marrow channeling.

METHODS

A systematic search of the Ovid MEDLINE, Embase, and Cochrane Library databases was conducted through mid January 2023. Two reviewers performed screening of studies meeting the eligibility criteria: English-language RCTs in patients aged ≥18 years comparing arthroscopic rotator cuff repair of full-thickness tears with and without bone marrow channeling (channeling group and control group, respectively). Functional scores, pain, healing rates, and reoperations were reviewed using pooled analysis where appropriate. The methodologic quality of included studies was assessed using the Cochrane risk-of-bias tool and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

RESULTS

A total of 6 randomized studies (N = 593) met the inclusion criteria. Pooled analysis of all 6 studies showed no significant mean difference in function (1.32; 95% confidence interval [CI], -0.63 to 3.26), as measured by the Constant-Murley score. Retear rates were also not statistically different between groups (risk ratio, 0.99; 95% CI, 0.57 to 1.71), with pooled retear rates of 19.6% (48 of 245) with channeling and 19.8% (51 of 257) without. The other outcomes of interest were only available for analysis in a subset of studies. There were no standardized mean differences in pain (0.09; 95% CI, -0.18 to 0.36), and there were similar reoperation rates (risk ratio, 1.19; 95% CI, 0.43 to 3.34) in the channeling and control groups. For the included studies, the overall quality of evidence by outcome was judged to be moderate (function, pain, and reoperations) or low (retear rates), mainly owing to risk of bias (all outcomes) and inconsistency (retear rates).

CONCLUSION

The results of this study refute the findings of prior systematic reviews that showed that channeling reduces the retear rate when combined with arthroscopic rotator cuff repair. This meta-analysis of level I evidence, including recent larger RCTs, demonstrates that bone marrow stimulation in the setting of primary arthroscopic rotator cuff repair has no significant effect on functional outcomes, healing, pain, or reoperation rates.

Intraoperative Channeling in Arthroscopic Rotator Cuff Repair: A Multicenter Randomized Controlled Trial

BACKGROUND

Despite recent advances in arthroscopic rotator cuff repair, the retear rate remains high. New methods to optimize healing rates must be sought. Bone channeling may create a quicker and more vigorous healing response by attracting autologous mesenchymal stem cells, cytokines, and growth factors to the repair site.

HYPOTHESIS

Arthroscopic rotator cuff repair with bone channeling would result in a higher healing rate compared with arthroscopic rotator cuff repair without adjuvant channeling.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

Our primary objective was to compare healing rates in patients undergoing arthroscopic rotator cuff repair for degenerative tears, with and without bone channeling. Secondary objectives included comparisons of the Western Ontario Rotator Cuff Index (WORC) score, American Shoulder and Elbow Surgeons (ASES) score, Constant score, Constant strength subscore, and visual analog scale (VAS) for pain score between groups. Patients undergoing arthroscopic rotator cuff repair were recruited at 3 sites and were randomized to receive either bone channeling augmentation or standard repair. Healing was determined via ultrasound at 24 months postoperatively. WORC, ASES, and Constant scores were compared between groups at baseline and at 3, 6, 12, and 24 months postoperatively.

RESULTS

A total of 168 patients were enrolled between 2013 and 2018. Intention-to-treat analysis revealed no statistical differences in healing rates between the 2 interventions at 24 months postoperatively. Statistically significant improvements occurred in both groups from preoperatively to all time points for the WORC, the ASES score, the Constant score or Constant strength subscore, and the VAS for pain (P < .0001). No differences were observed between the bone channeling and control groups in WORC, ASES, Constant, and VAS pain scores at any time point.

CONCLUSION

This trial did not demonstrate the superiority of intraoperative bone channeling in rotator cuff repair over standard rotator cuff repair at 24 months postoperatively. Healing rates, patient-reported function, and quality-of-life outcomes were similar between groups.

REGISTRATION

NCT01877772 (ClinicalTrials.gov identifier).

Position statement: nonoperative management of lateral epicondylitis in adults

We sought to compare methods of nonsurgical treatment of lateral epicondylitis in men and women older than 18 years to develop a guideline intended for orthopedic surgeons and other health care providers who assess, counsel and care for these patients. We searched Medline, Embase and Cochrane through to Mar. 9, 2021, and included all English-language studies comparing nonsurgical approaches. We compared physiotherapy versus no active treatment, corticosteroids versus placebo, platelet-rich plasma (PRP) versus placebo, and autologous blood injection versus placebo. Outcomes of interest were pain outcomes (visual analogue scale scores) and functional outcomes. We rated the quality of the evidence and strength of recommendations using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. This guideline will benefit patients seeking nonsurgical intervention for lateral epicondylitis by improving counselling on nonsurgical treatment options and possible outcomes. It will also benefit surgical providers by improving their knowledge of various nonsurgical approaches. Data presented could be used to develop frameworks and tools for shared decision-making.

A Multicenter Randomized Controlled Trial Comparing Single-Row With Double-Row Fixation in Arthroscopic Rotator Cuff Repair: Long-Term Follow-up

BACKGROUND

The long-term outcomes of single- versus double-row fixation in arthroscopic rotator cuff repair are not currently known.

PURPOSE

To compare the treatment effects of the single- versus double-row suture technique in arthroscopic rotator cuff repair of full-thickness tears at 10-year follow-up.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

Patients were evaluated at 10 years postoperatively. The primary outcome measure was the Western Ontario Rotator Cuff Index (WORC). Secondary outcome measures included the American Shoulder and Elbow Surgeons (ASES) score, Constant score, strength, and incidence of revision surgery. Ultrasound was used to evaluate the rotator cuff to determine repair integrity. Statistical analyses consistent with those of the main trial were conducted.

RESULTS

Of the original 90 participants, 77 (85%) returned at a mean follow-up of 10 years. At ten year follow-up, the WORC score was higher in the double row group (79.9 [95% CI, 16.2 to 99.1]) compared with the single row group (72.9, [95% CI, 4.3 to 100]), P = .020. From baseline to 2 years, the mean change in WORC scores for the single-row group was -48.5 compared with -40.6 for the double-row group, with a between-group difference of -7.8 (95% CI, -20.4 to 4.7). From 2 to 10 years, the change in WORC scores for the single-row group was 11.5 compared with -0.2 for the double-row group, with a between-group difference of 11.7 (95% CI, -0.7 to 24.3). From baseline to 10 years, the mean between-group difference was 3.9 (95% CI, -7.8 to 15.6). Similarly, a decrease in ASES scores was observed between 2 and 10 years for the single-row group (9.2 [95% CI, 0.9 to 17.5]; P = .029), with a nonsignificant decrease in ASES scores for the double-row group (6.2 [95% CI, -3.2 to 15.6]; P = .195) as well as a decrease in Constant scores for both the single- (9.5 [95% CI, 1.4 to 17.5]; P = .020) and double-row (14.4 [95% CI, 5.6 to 23.3]; P = .001) groups. Overall, 3 participants developed a full-thickness tear after 2 years: 2 from the double-row group and 1 from the single-row group. One participant from each study group underwent revision surgery after the 2-year time point.

CONCLUSION

A statistically significant (but likely not clinically important) difference in WORC scores was seen at 10-year follow-up in favor of double-row fixation. Between baseline and 10-year follow-up, a decrease in most outcome scores was observed in both the single- and the double-row groups.

REGISTRATION

NCT00508183 (ClinicalTrials.gov identifier).

The Use of Elbow Arthroscopy for Management of the Pediatric Elbow: A Systematic Review of Indications and Outcomes

PURPOSE

The purpose of this review was to systematically examine the literature surrounding elbow arthroscopy for pediatric patients and to assess indications, functional outcomes, and complication rates.

METHODS

This systematic review was carried out in accordance with PRISMA guidelines. EMBASE, PubMed, and MEDLINE were searched for relevant literature from inception until December 2019, and studies were screened by 2 reviewers independently and in duplicate for those investigating elbow arthroscopy in a pediatric population (<18 years). Editorials, review articles, and case reports were excluded. Demographic data and data on surgical indications, treatment outcomes, and complications were recorded. A methodological quality assessment was performed for all included studies using the Methodological Index for Non-Randomized Studies.

RESULTS

Overall, 19 studies, all of level IV evidence, were identified with a total of 492 patients (513 elbows). The patient population was 22.3% female with a mean age of 14.0 years (range, 4.0-15.7) and a mean follow-up time of 33.0 months (range, 7.4-96 months). Twelve studies (263 patients) exclusively recruited patients with osteochondritis dissecans (OCD), although other indications for elbow arthroscopy included arthrofibrosis (50 patients), elbow fracture (37 patients), medial ulnar collateral ligament injury (31 patients), and posterior impingement (17 patients). All 13 reporting studies showed a significant improvement in the elbow flexion-extension arc, and 4 of 5 that reported a functional outcome score before and after surgery demonstrating a significant improvement. Last, the overall complication rates ranged from 0% to 23.8%, with a total of 8 instances of neurological injury (5 ulnar, 2 radial, 1 unspecified), all being transient and resolving within 3 to 6 months.

CONCLUSION

Although elbow arthroscopy is primarily being performed for OCD in children and adolescents, there is evidence surrounding several other potential indications. Case series published to date have demonstrated significant improvements in functional outcomes and low rates of major complications.

LEVEL OF EVIDENCE

Level IV, systematic review of level IV studies.

Preoperative bone marrow stimulation does not improve functional outcomes in arthroscopic cuff repair: a prospective randomized controlled trial

AIMS

Despite recent advances in arthroscopic rotator cuff repair, re-tear rates remain high. New methods to improve healing rates following rotator cuff repair must be sought. Our primary objective was to determine if adjunctive bone marrow stimulation with channelling five to seven days prior to arthroscopic cuff repair would lead to higher Western Ontario Rotator Cuff (WORC) scores at 24 months postoperatively compared with no channelling.

METHODS

A prospective, randomized controlled trial was conducted in patients undergoing arthroscopic rotator cuff repair. Patients were randomized to receive either a percutaneous bone channelling of the rotator cuff footprint or a sham procedure under ultrasound guidance five to seven days prior to index surgery. Outcome measures included the WORC, American Shoulder and Elbow Surgeons (ASES), and Constant scores, strength, ultrasound-determined healing rates, and adverse events.

RESULTS

Overall, 94 patients were randomized to either bone channelling or a sham procedure. Statistically significant improvements in all clinical outcome scores occurred in both groups from preoperative to all timepoints (p < 0.001). Intention-to-treat analysis revealed no statistical differences in WORC scores between the two interventions at 24 months postoperatively (p = 0.690). No differences were observed in secondary outcomes at any timepoint and healing rates did not differ between groups (p = 0.186).

CONCLUSION

Preoperative bone channelling one week prior to arthroscopic rotator cuff repair was not associated with significant improvements in WORC, ASES, Constant scores, strength, or ultrasound-determined healing rates. Cite this article: Bone Joint J 2021;103-B(1):123-130.

Effectiveness of Immersive Virtual Reality on Orthopedic Surgical Skills and Knowledge Acquisition Among Senior Surgical Residents: A Randomized Clinical Trial

IMPORTANCE

Video learning prior to surgery is common practice for trainees and surgeons, and immersive virtual reality (IVR) simulators are of increasing interest for surgical training. The training effectiveness of IVR compared with video training in complex skill acquisition should be studied.

OBJECTIVES

To evaluate whether IVR improves learning effectiveness for surgical trainees and to validate a VR rating scale through correlation to real-world performance.

DESIGN, SETTING, AND PARTICIPANTS

This block randomized, intervention-controlled clinical trial included senior (ie, postgraduate year 4 and 5) orthopedic surgery residents from multiple institutions in Canada during a single training course. An intention-to-treat analysis was performed. Data were collected from January 30 to February 1, 2020.

INTERVENTION

An IVR training platform providing a case-based module for reverse shoulder arthroplasty (RSA) for advanced rotator cuff tear arthropathy. Participants were permitted to repeat the module indefinitely.

MAIN OUTCOMES AND MEASURES

The primary outcome measure was a validated performance metric for both the intervention and control groups (Objective Structured Assessment of Technical Skills [OSATS]). Secondary measures included transfer of training (ToT), transfer effectiveness ratio (TER), and cost-effectiveness (CER) ratios of IVR training compared with control. Additional secondary measures included IVR performance metrics measured on a novel rating scale compared with real-world performance.

RESULTS

A total of 18 senior surgical residents participated; 9 (50%) were randomized to the IVR group and 9 (50%) to the control group. Participant demographic characteristics were not different for age (mean [SD] age: IVR group, 31.1 [2.8] years; control group, 31.0 [2.7] years), gender (IVR group, 8 [89%] men; control group, 6 [67%] men), surgical experience (mean [SD] experience with RSA: IVR group, 3.3 [0.9]; control group, 3.2 [0.4]), or prior simulator use (had experience: IVR group 6 [67%]; control group, 4 [44%]). The IVR group completed training 387% faster considering a single repetition (mean [SD] time for IVR group: 4.1 [2.5] minutes; mean [SD] time for control group: 16.1 [2.6] minutes; difference, 12.0 minutes; 95% CI, 8.8-14.0 minutes; P < .001). The IVR group had significantly better mean (SD) OSATS scores than the control group (15.9 [2.5] vs 9.4 [3.2]; difference, 6.9; 95% CI, 3.3-9.7; P < .001). The IVR group also demonstrated higher mean (SD) verbal questioning scores (4.1 [1.0] vs 2.2 [1.7]; difference, 1.9; 95% CI, 0.1-3.3; P = .03). The IVR score (ie, Precision Score) had a strong correlation to real-world OSATS scores (r = 0.74) and final implant position (r = 0.73). The ToT was 59.4%, based on the OSATS score. The TER was 0.79, and the system was 34 times more cost-effective than control, based on CER.

CONCLUSIONS AND RELEVANCE

In this study, surgical training with IVR demonstrated superior learning efficiency, knowledge, and skill transfer. The TER of 0.79 substituted for 47.4 minutes of operating room time when IVR was used for 60 minutes.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04404010.

Glenoid exposure in shoulder arthroplasty: the role of soft tissue releases

Background

The deltopectoral approach is commonly used in shoulder arthroplasty. Various soft tissue releases can be performed to obtain adequate glenoid exposure, but their effectiveness is not known. The purpose of this study was to (1) quantify the effects of various releases on the amount of glenoid surface area exposure and (2) determine if common soft tissue releases performed about the shoulder significantly improve exposure of the glenoid.

Methods

A standard deltopectoral approach was used on cadaveric shoulders (n=8) in the beach chair position. The releases performed were as follows: long head of biceps, pectoralis major tendon, inferior capsule, and posterior capsule. Following each release, a custom-designed jig was used to mark the exposed glenoid surface. The glenoid was then digitized using a 3D surface scanner to quantify the exposed surface area with each release.

Results

The mean glenoid surface area exposure prior to any releases was 57% (SD 8%). Following release of the long head of biceps, exposure increased to 69% (SD 10%). The exposed area was increased to 83% (SD 6%) with release of the pectoralis major, and 93% (SD 2%) with inferior capsule. The entire glenoid was exposed following posterior capsule release.

Conclusions

Release of the long head of biceps, pectoralis major, and inferior and posterior capsule all independently led to significant increases in glenoid surface exposure in the deltopectoral approach. Mean surface area exposed with all 3 releases was 93%. Although posterior capsular release improved exposure, the results of this study suggest that this is rarely necessary.

Lateral Trochlear Ridge: A Non-Articulating Zone for Anterior-to-Posterior Screw Placement in Fractures Involving the Capitellum and Trochlea

BACKGROUND

Coronal shear fractures of the distal aspect of the humerus that involve the capitellum and the trochlea are rare; nevertheless, they are difficult to treat because of the complex fracture patterns and osteochondral nature of the fragments, limiting optimal screw placement. The use of anterior-to-posterior screw fixation by a lag technique (without countersinking) could potentially improve the strength of the construct. Our primary research question was to anatomically determine if there is a non-articulating zone for screw placement along the anterior aspect of the lateral trochlear ridge (aLTR) throughout normal elbow range of motion.

METHODS

Eight fresh-frozen cadaveric elbows were used. The region of interest was defined with 3 polymeric pins inserted in the inferior, middle, and superior-most aspects of the aLTR of each elbow, with use of an extensor digitorum communis (EDC) split approach. The elbows were then mounted on a magnetic resonance imaging (MRI)-compatible compression frame and subjected to high-resolution 7-T MRI at 90°, 120°, and 145° of flexion (positions of potential impingement), and at neutral and maximal pronation and maximal supination for each position of flexion. Portions of the aLTR that had free adjacent space were identified using the sagittal and coronal scans. This non-articulating region was identified as the "non-articulating zone" (NAZ).

RESULTS

The NAZ was found to encompass the proximal 38.2% (range, 30.2% to 48.9%) of the aLTR, measuring, on average, 5.2 mm in width. It was consistently located either directly adjacent to the apex of the ridge or just medial to it. The distal 61.8% of the aLTR articulated with either the ulna or the radial head in some of the elbows.

CONCLUSIONS

Our results suggest that there is a portion of the aLTR that, despite being covered with articular cartilage, is non-articulating throughout normal elbow range of motion.

CLINICAL RELEVANCE

In situations in which headless anterior-to-posterior and posterior-to-anterior screw insertion results in inadequate fixation of capitellar-trochlear fractures, anterior-to-posterior lag screw instrumentation along the non-articulating portion of the aLTR may provide a location for additional fixation in some patients. However, because of variation between patients, each case must be individualized.

Ramsey Spectroscopy with Displaced Frequency Jumps

Sophisticated Ramsey-based interrogation protocols using composite laser pulse sequences have been recently proposed to provide next-generation high-precision atomic clocks with a near perfect elimination of frequency shifts induced during the atom-probing field interaction. We propose here a simple alternative approach to the autobalanced Ramsey interrogation protocol and demonstrate its application to a cold-atom microwave clock based on coherent population trapping (CPT). The main originality of the method, based on two consecutive Ramsey sequences with different dark periods, is to sample the central Ramsey fringes with frequency jumps finely adjusted by an additional frequency-displacement concomitant parameter, scaling as the inverse of the dark period. The advantage of this displaced frequency-jump Ramsey method is that the local oscillator (LO) frequency is used as a single physical variable to control both servo loops of the sequence, simplifying its implementation and avoiding noise associated with controlling the LO phase. When tested using a CPT cold-atom clock, the DFJR scheme reduces the sensitivity of the clock frequency to variations of the light shifts by more than an order of magnitude compared with the standard Ramsey interrogation. This simple method can be applied in a wide variety of Ramsey-spectroscopy based applications including frequency metrology with CPT-based and optical atomic clocks, mass spectrometry, and precision spectroscopy.

A randomized, double-blind sham-controlled trial on the efficacy of arthroscopic tennis elbow release for the management of chronic lateral epicondylitis

BACKGROUND

Tennis elbow is a common elbow pathology typically affecting middle-aged individuals that can lead to significant disability. Most cases resolve within 2 years of symptom onset, but a subset of patients will develop persistent symptoms despite appropriate conservative management. There are several surgical approaches used to treat chronic tennis elbow, with arthroscopic surgery becoming an increasingly popular approach to address this pathology in North America. This procedure involves the arthroscopic release of the extensor carpi radialis brevis tendon (ECRB) origin at the elbow. The potential benefit of arthroscopic treatment of this condition is improved patient outcomes and shorter recovery time following surgery. The results of this technique have been reported only in the context of case series, which have shown positive results. However, in order to justify its widespread use and growing popularity, a high level of evidence study is required. The purpose of this prospective, randomized sham-controlled trial is to determine whether arthroscopic tennis elbow release is effective at treating chronic lateral epicondylitis.

METHODS

We will conduct a prospective single center, double-blind, randomized sham-controlled parallel arm trial evaluating the efficacy of arthroscopic tennis elbow release in adult patients with symptoms for at least 6 months. Patients will undergo intraoperative randomization after diagnostic arthroscopy of the elbow to receive either ECRB release (through the creation of a lateral portal) or a sham lateral portal and no ECRB release. The primary outcome will be the Mayo Elbow Performance Score (MEPS) at 1 year follow-up. Secondary outcomes will be the abbreviated Disability of the Shoulder and Hand (DASH) score, American Shoulder and Elbow Surgeons elbow (ASES-e) score and grip strength at 3, 6, 12 and 24 months as well as return-to-work time, ability to return to full duty and adverse outcomes.

DISCUSSION

Results of this study will provide empirical high quality evidence to guide clinical decision-making in patients with chronic tennis elbow.

TRIAL REGISTRATION

NCT02236689 (September 8, 2014).

The effect of implant malalignment on joint loading in total elbow arthroplasty: an in vitro study

HYPOTHESIS

Aseptic loosening is one of the leading causes of failure in total elbow arthroplasty. Incorrect implant positioning and alignment in other joints such as the knee have been found to lead to excessive loading and wear. Although similar alignment difficulties exist in the elbow, the effect of implant malalignment on wear-inducing loads is not yet known. This in vitro study determined the effect of anterior malpositioning and varus-valgus and internal-external malrotations on humeral stem loading in total elbow arthroplasty.

METHODS AND MATERIALS

Computer-navigated linked elbow arthroplasty was conducted in 8 cadaveric elbows. A modular, instrumented humeral component was used to measure loading during simulated elbow motion while the position of the ulna relative to the humerus was recorded.

RESULTS

Loading increased for all malaligned implant positions tested (P < .05). During simulation of implant malpositioning, combinations of internal-external and varus-valgus malrotations that tended to preserve the line of action of the elbow flexors had lower loads than combinations that did not.

DISCUSSION

This in vitro study showed that loading does increase after humeral component malalignment; however, further studies are required to determine the long-term effects on polyethylene wear and component loosening.

Kinematics and laxity of a linked total elbow arthroplasty following computer navigated implant positioning

Aseptic loosening in total elbow arthroplasty (TEA) remains the most common cause of long-term failure. While several different mechanisms of implant loosening have been suggested, it is likely that one important underlying cause is implant malpositioning, resulting in changes in joint kinematics and loading. Although use of computer navigation has been shown to improve component positioning in other joints, no such system currently exists for the elbow. This study used real-time computer feedback for humeral, ulnar, and radial component positioning in 11 cadaveric extremities. An elbow motion simulator evaluated joint kinematics. Endosteal abutment of the stems of the humeral and ulnar components precluded optimal positioning in 5 and 6 specimens, respectively. Loss of the normal valgus angulation following elbow arthroplasty (p < 0.05) suggests that errors in humeral component positioning translate directly into changes in joint kinematics during active motion. These findings suggest that although computer navigation can reproduce normal joint kinematics, optimal implant positioning may require a TEA system which allows for some modularity to accommodate the normal variations in osseous morphology of the elbow.

Is bacterial vaginosis associated with cervical intraepithelial neoplasia?

Previous research has produced conflicting results regarding the association of bacterial vaginosis (BV) and cervical intraepithelial neoplasia (CIN). These studies have been weakened in their conclusions mainly by failure to adequately control for the presence of sexually transmitted infections (STIs). One proposed mechanism suggesting that carcinogenic nitrosamines acting either independently or via human papilloma virus (HPV) has not been fully tested previously. We undertook a prospective, case-controlled, cross-sectional study where the presence of STIs, in particular human papillomavirus (HPV) which is known to be associated with the development of CIN, was controlled for. Women with BV were not found to have CIN more frequently than women with normal vaginal flora and the quantities of nitrosamines produced by women with BV did not differ significantly from women without BV. We thus found that BV is not associated with CIN.

Is bacterial vaginosis associated with cervical intraepithelial neoplasia?

Previous research has produced conflicting results regarding the association of bacterial vaginosis (BV) and cervical intraepithelial neoplasia (CIN). These studies have been weakened in their conclusions mainly by failure to adequately control for the presence of sexually transmitted infections (STIs). One proposed mechanism suggesting that carcinogenic nitrosamines acting either independently or via human papilloma virus (HPV) has not been fully tested previously. We undertook a prospective, case-controlled, cross-sectional study where the presence of STIs, in particular human papillomavirus (HPV) which is known to be associated with the development of CIN, was controlled for. Women with BV were not found to have CIN more frequently than women with normal vaginal flora and the quantities of nitrosamines produced by women with BV did not differ significantly from women without BV. We thus found that BV is not associated with CIN.