Due to the large volume of feedback received in response to the previously published Veterinary Practice News article on canine cruciate surgery, it is clear that some confusion exists regarding our current clinical management of patients with canine cruciate ligament disease (CCLD). Recognizing that there are, unfortunately, large knowledge gaps regarding the clinical efficacy of many treatments for this disease, we do our best to tailor our treatment recommendations to the specific needs of the patient and pet owner.
While in some instances this may mean a non-surgical therapy approach, surgical treatment is provided as a component of the overall patient care for the majority of patients presented to the orthopedic service. Nonetheless, we prefer not to think about CCLD patient care (or clinical research) in terms of a simple “surgical versus non-surgical” dichotomous relationship; instead, we prefer the integrative approach of determining the best combination/choice of surgical, pain management, rehabilitation and complementary medicine techniques.
The most important question we should ask ourselves is: “Which treatment combinations can provide the best long-term quality of life?” Obviously, the answer to this question differs based on patient signalment and athleticism, concurrent disease and owner’s expectations. The goal of this follow-up article is to address some of the questions raised and to provide the reader with an outline of the decision process that is currently utilized at Colorado State University when evaluating available treatment options for CCLD.
Although it is debated whether surgical treatment of ACL injuries is superior to conservative treatment in people, greater knee stability, greater athletic ability and reduced risk of meniscal injuries are frequently cited benefits of surgery.1-5 While these are likely important considerations for the canine patient as well, caution is advised when extrapolating human data to the treatment of animals. This is particularly difficult because of the different pathogenesis of the disease and the greater tibial plateau angle observed in our canine patients as compared to humans. In fact, the canine knee after tibial plateau leveling osteotomy somewhat resembles the human knee and therefore one could argue that TPLO bears some biomechanical resemblance to conservative treatment in people.
Surgical treatment of CCLD with various treatment methods has been shown to improve limb function and result in high owner satisfaction in numerous studies.6-10 However, many studies have design limitations that include low patient numbers, short-term follow-up, lack of a control group, and suboptimal outcome measures (owner questionnaire, orthopedic exam, or subjective lameness grading).
Until better designed clinical studies provide definitive answers to our everyday questions, evidence-based decision-making is admittedly limited and must, by default, be supported by subjective clinical experience.
With regard to available evidence, three recent in vivo studies have shown that TPLO can restore canine kinematic data to near normality11-13 and in a study of 1,000 consecutive dogs undergoing TPLO surgery, no catastrophic implant failure was observed.14 Furthermore, all complications (such as infection, meniscal injury) observed in this study resolved after a second intervention (plate removal, meniscectomy).
Two studies evaluating non-surgical treatment found inferior owner outcome scoring for dogs treated non-surgically when compared to lateral fabellar suture15 and improvement of lameness in only 19.3 percent of the dogs with a body weight of 15 kg or greater.16 It must be stated that just as surgical care for CCLD has evolved over time, so has “non-surgical/conservative” care. Whereas non-surgical care once consisted of little more than rest and anti-inflammatories, these same animals today would often be treated with acupuncture, laser and/or physical rehabilitation.
To the authors’ knowledge, there is no current short- or long-term clinical evidence supporting any alternative treatment option (such as acupuncture, laser or rehabilitation) alone for CCLD. However, available research suggests that postoperative rehabilitation combined with management of osteoarthritis greatly benefit the patient with CCLD.
Therefore, surgery in combination with these treatments should be offered to owners as the treatment of choice for most dogs until the outcome of alternative treatments by themselves has been clinically evaluated. When surgical treatment is either contraindicated or not feasible, reliance upon these treatment modalities obviously assumes even greater importance.
Rehabilitation for treatment of CCLD is recommended for all patients undergoing surgical treatment of CCLD.8,17,18 However, it may also be used as a conservative treatment option for patients with co-morbidities that prevent surgery or for clients who elect a conservative approach. The goal of either treatment approach is functional optimization by enhancement of muscular stabilization of the CCLD stifle while maintaining the ligamentous integrity of the contralateral stifle.19 Treatment recommendations for CCLD may be based on the degree of injury to the cruciate ligament, similar to recommendations for humans.20
A commonly used grading system among physical therapists classifies patients into three levels, depending on severity of CCL damage. These are defined as: Grade I, pain with no significant cranial drawer instability; Grade II, pain with cranial drawer instability; and Grade III, no pain with severe cranial drawer instability.
Based on clinical outcomes experienced by one of the authors (SF), Grade I and II sprains can be successfully returned to full function including hiking, running and agility with a four- to six-month rehabilitation program that includes strength training, motor timing and motor control exercises. Grade III sprains can only be returned to limited function including walking and household activities with a similar treatment regimen completed while the knee is supported with a brace or wrap.
For post-operative canine patients, rehabilitation has been shown to accelerate recovery.17 Our current post-operative rehabilitation includes three phases that span 12 weeks. Each phase emphasizes client education for adherence to the medical and physical therapy protocols and a home exercise program that, in the human model, has been shown to decrease the risk of injury after surgery.21 Phase I emphasizes edema and pain management.22,23 Phase II initiates proprioceptive and strengthening exercises24-27 and Phase III initiates exercises to support return to full functional activity.28
The Integrative Approach
Integrative medicine for CCLD focuses on reinforcing endogenous recuperative mechanisms. Whether or not a patient undergoes surgery, integrative medicine may facilitate return to function and reduction in pain in many ways.
Laser therapy modulates the inflammatory process and reduces edema, leukocyte influx, myeloperoxidase activity and a variety of pro-inflammatory mediators.29 In the event of concomitant meniscal pathology, LT stimulates fibroblastic and fibrochondrondrocyte proliferation along with angiogenesis while it may inhibit pain provoked by irritated intrameniscal nociceptors.30
Exercise therapy produces significant improvement in knee function early after ACL injury in humans.31 LT supports this exercise retraining by improving endurance and reducing fatigue in the extensor muscles of the knee.32 A recent study showed that laser therapy promoted better function and analgesia in humans with knee osteoarthritis.33,34 Massage works well alongside laser to reduce pain and decrease flexion contracture or trigger point formation that alter biomechanics in the knee.35
Acupuncture also offers a spectrum of clinically valuable, cost-effective benefits for the injured knee.36,37 A review of 10 trials representing nearly 1,500 human patients concluded that acupuncture significantly reduces pain and physical dysfunction.38 Acupuncture directed toward trigger points may be more effective than standard acupuncture or sham treatment.39 Dry needling (i.e., stimulation with needles alone) addresses local, referred, and generalized pain. By eliminating long-standing nociceptive input from trigger point pathology, acupuncture helps reverse central sensitization. Dry needling also restores range of motion, tissue homeostasis, and proper muscle activation patterns.40 In people, continued joint laxity does not mean that conservative management has failed. ACL-deficient human patients treated non-operatively demonstrated significantly more joint laxity than pair-matched cohorts who received surgery, but exhibited higher performance on hop test limb symmetry indices, activity daily living scores, and other subjective scores.41
As integrative medicine continues to build upon its scientific basis and evidence of effectiveness, the question of what constitutes “standard of care” arises. China is currently grappling with these issues as traditional medicine meets modern science.42 Even though some practitioners in China as well as North America may advocate setting lower standards for integrative therapies, it is our view that both complementary and conventional medicine should adhere to the same standards.
We, as a profession, should strive to determine best practices through clinical research instead of basing what we teach and practice on opinion and tradition. Unfortunately, the knowledge gaps with regard to clinical outcomes of these various surgical and non-surgical treatments in dogs with naturally occurring CCLD are vast and the need for well designed, long-term, prospective, randomized, controlled clinical studies is clear.
Dr. Robinson, DVM, DO, Dipl. ABMA, FAAMA, oversees complementary veterinary education at Colorado State University.
3. Sanchez-Bustinduy M, de Medeiros MA, Radke H, et al: Comparison of kinematic variables in defining lameness caused by naturally occurring rupture of the cranial cruciate ligament in dogs. Vet Surg 39:523-530, 2010.
5. Meuffels DE, Favejee MM, Vissers MM, et al: Ten year follow-up study comparing conservative versus operative treatment of anterior cruciate ligament ruptures. A matched-pair analysis of high level athletes. Br J Sports Med 43:347-351, 2009.
6. Lafaver S, Miller NA, Stubbs WP, et al: Tibial tuberosity advancement for stabilization of the canine cranial cruciate ligament-deficient stifle joint: surgical technique, early results, and complications in 101 dogs. Vet Surg 36:573-586, 2007.
8. Au KK, Gordon-Evans WJ, Dunning D, et al: Comparison of short- and long-term function and radiographic osteoarthrosis in dogs after postoperative physical rehabilitation and tibial plateau leveling osteotomy or lateral fabellar suture stabilization. Vet Surg 39:173-180, 2010.
9. Gatineau M, Dupuis J, Plante J, et al: Retrospective study of 476 tibial plateau levelling osteotomy procedures. Rate of subsequent 'pivot shift', meniscal tear and other complications. Vet Comp Orthop Traumatol 24:333-341, 2011.
10. Cook JL, Luther JK, Beetem J, et al: Clinical comparison of a novel extracapsular stabilization procedure and tibial plateau leveling osteotomy for treatment of cranial cruciate ligament deficiency in dogs. Vet Surg 39:315-323, 2010.
11. de Medeiros M, Sanchez Bustinduy M, Radke H, et al: Early kinematic outcome after treatment of cranial cruciate ligament rupture by tibial plateau levelling osteotomy in the dog. Vet Comp Orthop Traumatol 24:178-184, 2011.
12. Boddeker J, Druen S, Meyer-Lindenberg A, et al: Computer-assisted gait analysis of the dog: comparison of two surgical techniques for the ruptured cranial cruciate ligament. Vet Comp Orthop Traumatol 25:11-21, 2012.
14. Fitzpatrick N, Johnson J, Hayashi K, et al: Tibial plateau leveling and medial opening crescentic osteotomy for treatment of cranial cruciate ligament rupture in dogs with tibia vara. Vet Surg 39:444-453, 2010.
15. Chauvet AE, Johnson AL, Pijanowski GJ, et al: Evaluation of fibular head transposition, lateral fabellar suture, and conservative treatment of cranial cruciate ligament rupture in large dogs: a retrospective study. J Am Anim Hosp Assoc 32:247-255, 1996.
16. Vasseur PB, Rodrigo JJ, Stevenson S, et al: Replacement of the anterior cruciate ligament with a bone-ligament-bone anterior cruciate ligament allograft in dogs. Clin Orthop Relat Res:268-277, 1987.
17. Monk ML, Preston CA, McGowan CM: Effects of early intensive postoperative physiotherapy on limb function after tibial plateau leveling osteotomy in dogs with deficiency of the cranial cruciate ligament. Am J Vet Res 67:529-536, 2006.
18. Gordon-Evans WJ, Dunning D, Johnson AL, et al: Randomised controlled clinical trial for the use of deracoxib during intense rehabilitation exercises after tibial plateau levelling osteotomy. Vet Comp Orthop Traumatol 23:332-335, 2010.
21. Di Monaco M, Vallero F, De Toma E, et al: A single home visit by an occupational therapist reduces the risk of falling after hip fracture in elderly women: a quasi-randomized controlled trial. J Rehabil Med 40:446-450, 2008.
23. Drygas KA, McClure SR, Goring RL, et al: Effect of cold compression therapy on postoperative pain, swelling, range of motion, and lameness after tibial plateau leveling osteotomy in dogs. J Am Vet Med Assoc 238:1284-1291, 2011.
24. Johnson JM, Johnson AL, Pijanowski GJ, et al: Rehabilitation of dogs with surgically treated cranial cruciate ligament-deficient stifles by use of electrical stimulation of muscles. Am J Vet Res 58:1473-1478, 1997.
27. Eriksson E, Haggmark T: Comparison of isometric muscle training and electrical stimulation supplementing isometric muscle training in the recovery after major knee ligament surgery. A preliminary report. Am J Sports Med 7:169-171, 1979.
31. Eitzen I, Moksnes H, Snyder-Mackler L, et al: A progressive 5-week exercise therapy program leads to significant improvement in knee function early after anterior cruciate ligament injury. J Orthop Sports Phys Ther 40:705-721, 2010.
32. Vieira WH, Ferraresi C, Perez SE, et al: Effects of low-level laser therapy (808 nm) on isokinetic muscle performance of young women submitted to endurance training: a randomized controlled clinical trial. Lasers Med Sci 27:497-504, 2012.
37. Mavrommatis CI, Argyra E, Vadalouka A, et al: Acupuncture as an adjunctive therapy to pharmacological treatment in patients with chronic pain due to osteoarthritis of the knee: a 3-armed, randomized, placebo-controlled trial. Pain 153:1720-1726, 2012.
41. Grindem H, Eitzen I, Moksnes H, et al: A pair-matched comparison of return to pivoting sports at 1 year in anterior cruciate ligament-injured patients after a nonoperative versus an operative treatment course. Am J Sports Med 40:2509-2516, 2012.