Written by a CuraCore Veterinary Medical Acupuncture course graduate. Signed release obtained from client/author. 10D2018022
A 16-year-old Thoroughbred mare presented for lameness and stiffness to bend to the left while under saddle. Physical and myofascial examination revealed a right front lameness from a chronic injury, left cervical and shoulder pain. She was treated with acupuncture (dry needling and electroacupuncture) and massage, which improved her lameness, cervical flexibility and overall behavioral tension. Further recommendations and owner education focused on ongoing rehabilitation exercise and flexibility stretches.
History and Presentation:
“Allie”, a 16-year-old Thoroughbred mare, was presented for stiffness under saddle to the left and a loss of enthusiasm for her work. She is normally used as a dressage and hunter riding-lesson horse and typically seems to enjoy her job and her pupils until about a month prior to presentation. Additionally, for the last 5-6 months her riders and trainers have described that she is stiff to bend and difficult to hold a collected frame when traveling to the left. Since she is also a spirited mare when turned out in the paddock, approximately two months ago she sustained a laceration over her right carpus (full thickness skin laceration, without joint involvement), which has been slow to heal completely due to location. Currently, the wound has closed but subdermal scar tissue was palpated. She is now in light work consisting of walking under saddle with 10 minutes of trot, 3-4 times per week. She has maintained a good appetite for feed, demonstrates normal water consumption, and produces normal urine and manure of an expected amount. She is up-to-date on vaccinations against influenza, rhinopneumonitis, Eastern and Western encephalitis, tetanus and West Nile virus. She is dewormed twice a year and routine fecal parasite evaluations have all been negative. She has not traveled in the last year. Prior to acquisition as a riding-lesson horse she was used for intermediate level three-day eventing.
Physical Examination and Clinical Assessments:
On physical examination, she was bright, alert and responsive. She had a healthy hair coat and ideal body condition score (5/9). She appeared normally hydrated and systemically stable evidenced by normal jugular fill and mucous membrane color, moisture, and capillary refill time, and normal digital pulses. Heart rate (36 beats/min), respiratory rate (12 breaths/min) and rectal temperature (99.9 F) were all within normal limits. No nasal or ocular discharge was present. She had normal cardiothoracic auscultation, with no murmurs or arrhythmias appreciated, and normal borborygmi in all four abdominal quadrants. Musculoskeletal exam identified mild muscular asymmetry and atrophy on the left side of the neck (m. splenius, m. serratus ventralis cervicis, m. cervicalis mi. trapezii), and a positive pain response on palpation and gentle manipulation of her cervical spine. Generalized swelling was appreciated over her right carpus characterized by thickened firm tissue, consistent with scar tissue, and she was sensitive to moderate palpation pressure of this area. Mild tendon sheath effusion was present at the level of the fetlock in all four limbs that was cool and non-painful. Neurologic examination revealed normal cranial nerve responses. Neck flexion was moderately reduced to the left when asked to flex laterally without the enticement of a treat, but was symmetrical to the right and left with the assistance of a treat. Neck ventral-flexion and extension was normal. Cervicofacial response and panniculus reflex were both intact and symmetrical. She had normal tail and anal tone. Gait evaluation revealed a grade 3/5 lameness on the right front limb that appeared to localize to the carpus on flexion exam. No evidence of ataxia or proprioceptive deficits was present when evaluating her at the walk, trot, and tight circles. Myofascial examination revealed no pain response to lateral manipulation of the dorsal spinous processes of the withers, and no pain was elicited on lateral flexion of the thoraco-lumbar dorsal spinous processes. She demonstrated normal sacral pressure responses bilaterally, and normal ventral abdominal flexion in response to ventral abdominal pressure. She had normal balance upon lifting all four feet, except mild stiffness or reluctance to full flexion of the right front carpus. Front limb protraction was not successful due to refractoriness of the patient and it could not be definitively determined if this was behavioral or due to discomfort. She demonstrated sensitivity to palpation of ST7, both unilaterally and concurrently, BL10(left), TH17(left), LI18(left), LI16(left), SI9(left).
AlliePre-tx.walk AlliePre-tx.trot
Differential Diagnosis:
1) Ddx for stiffness under saddle to the left, cervical muscle atrophy, reluctance to flex cervical spine laterally, myofascial sensitivity to BL10(left), TH17(left), LI18(left), LI16(left), ST7(bilat): Osteoarthritis (OA) of the cervical spine facets, left CN 11 (accessory spinal nerve) dysfunction, cervical spine abscess, relative muscle hypertrophy of the right due to chronic guarding of the use of the right front limb and subsequent stiffness to the left, radiculopathy (cervical spinal nerve root compression/inflammation). Other less likely differentials include fibrocartilaginous embolism, cervical spine neoplasm (hemangiosarcoma, lymphoma), poor rider posture and chronic imbalance, Wobbler’s syndrome, immune-mediated myositis, cervical trauma, Cushing’s syndrome
2) Ddx for right front lameness, dorsal carpal swelling, pain on palpation: slow-healing carpal laceration with the development of scar tissue causing tension, neuropathic pain, OA of the right front carpus. Other less likely differentials include vascular injury of arterial branches of the brachial artery, septic carpal arthritis, soft tissue sarcoma, synovitis from synovial structure penetration, osteochondrosis dessicans, polysynovitis secondary to Lyme disease.
3) Ddx for myofascial sensitivity to LI16(left), SI9(left): chronic overuse of the contralateral limb (left front limb) to reduce pain in the right front
Medical Decision-Making:
Based on this mare’s history, physical examination and myofascial palpation exam acupuncture was offered as a treatment modality that might allow evasion, or a decreased dose, of non-steroidal anti-inflammatory drug (NSAID) which might be used to alleviate the pain and soreness in her neck and during the recovery of her right front limb injury. Further diagnostics were recommended and included imaging such as right front carpal radiographs (none taken at the time the injury occurred), cervical radiographs, and perhaps nuclear scintigraphy in order to confirm suspected differential diagnoses.
Initial goals of acupuncture therapy would be to utilize her autonomic nervous system (ANS) to suppress increased sympathetic tone, present due to pain in her cervical spine and right front forelimb, and increase parasympathetic tone in order promote healing, relieve tension and restore homeostasis through neuromodulation. Secondly, acupuncture would be used locally in regions of demonstrated sensitivity to neuromodulate spinal segments responsible for her cervical spine and front limbs. In addition, after each acupuncture treatment effleurage/massage would be performed over her cervical spine, shoulders and back to relieve myofascial tension accumulated due to front end overuse or guarding.
Acupuncture Treatments and Related Techniques:
Each acupuncture session started with Bai Hui, which promoted visible relaxation. After approximately 3-5 minutes, the remainder of the needles were placed, which did on occasion cause stimulation of certain points. Due to this reactivity, electroacupuncture was not initiated until the final session.
Treatment #1) Dry needling; ST7(bilat), BL10(left), TH16(left), LI18(left), GB21(left), BL11(left), SI9(bilat), LU1(left), ST36(bilat), Bai Hui. Seirin needles (0.20 x 30mm) were used on for all points, except ST7 which was treated with 0.16 x 15mm needles. The treatment lasted approximately 10 minutes. Bai Hui and ST36 were points used to neuromodulate the parasympathetic autonomic nervous system, while BL10, TH17, LI18, GB21, BL11, LU1, SI9 were local (and sensitive) points used to target spinal segments of the cervical spine and cranial thorax.
Treatment #2) Dry needling; GV20, BL10(bilat), Th16(left), LI18(left), LI16(left), SI9(bilat), LI11(bilat), Bai Hui, BL26(bilat), ST7(bilat), LU1(bilat), BL11(left), ST36(bilat). Seirin needles (0.25 x 30mm) were used for all points except GV20, LI11, ST36, ST7. GV20 and ST7 were treated with 0.16 x 15mm needles and LI11, ST36, and LU1 were treated with 0.2 x 30mm needles. This treatment also lasted approximately 10 min, although some needles fell out sooner than this time. The same ANS points were used with an addition of GV20, however additional local points were added either due to increased sensitivity to palpation on this day’s exam or to augment the points from the previous treatment; and improved patient compliance allowed for this extra treatment.
Treatment #3) Dry needling; GV20, BL10(bilat), Th16(left), LI18(left), LI16(left), SI9(bilat), LI11(bilat), Bai Hui, ST7(bilat), LU1(bilat), BL11(left), ST36(bilat). Seirin needles (0.25 x 30mm) were used for all points except GV20, LI11, ST36, ST7. GV20 and ST7 were treated with 0.16 x 15mm Seirin needles and LI11, ST36, and LU1 were treated with 0.2 x 30mm needles. For this treatment electroacupuncture (EAP) was added (Ito unit, medium setting, frequency setting 6 (2-2.5 Hz), continuous, using 2 channels) with the goal of mediating endorphin release with a lower frequency to treat pain and muscle spasm. The points used for EAP were focused over the left cervical region and included TH16 with LI18, and BL11 with LI16 in a box pattern (using 2 channels). This EAP treatment lasted for approximately 10-11 minutes. Total acupuncture treatment was approximately 15-20 minutes.
Rehabilitative Recommendations:
Although controversial, it was also recommended to keep the mare in light work while providing analgesic support via acupuncture and, if needed, NSAIDs to promote usage of her whole body equally and balanced, and minimize further muscle atrophy. In addition, the firm tissue swelling over the dorsum of her right carpus was suspected to be scar tissue for which the restrictions would benefit from low-grade continued movement and flexion. And finally, she is a high-energy mare for which complete restricted exercise would be mentally detrimental to her well-being.
The owner was also shown stretching exercises her pupils could continue with her 3-4 times per week after her exercise session to promote flexibility and mobility of all joints, but especially her cervical spine and shoulders (Stubbs and Clayton, 2008).
AlliePost-tx.walk AlliePost-tx.trot
Outcomes, Discussion:
“Allie” presented with multiple sources of musculoskeletal pain and myofascial tension. As a riding lesson horse, it is not unusual for her to be ridden by people who have less control of their riding posture resulting in extra strain and stress on structures such as the thoracolumbar and shoulder region, and additional strain compensation by the neck. While she clearly demonstrated sources of pain and responsiveness in her neck, and shoulder on the left side, it was a little surprising that she was as comfortable and flexible in her lumbar sacral region as she was based on the work she does. Nevertheless, for these initial three acupuncture sessions we focused on specific regions of discomfort in hopes to neuromodulate spinal segments, treat local pain, and improve mobility which has been restricted by her chronic right carpal injury. In a study where 18 horses diagnosed with cervical stiffness were divided into a treatment and control group and treated with electroacupuncture, the horses in the treatment group showed significant improvement in two lateral bend measurements over the control group (Pasteur, 2017). Over the course of these treatments she improved from a grade 3/5 lameness in the right front to a 2/5 lameness in the right front despite not treating her right carpus directly. Additionally, while the initial acupuncture treatment was a little stressful for her, subsequent sessions improved her attitude and relaxation substantially. To mitigate this in the future, I might reach for slightly smaller diameter needles for the first session, knowing that she is a high-energy Thoroughbred mare possibly falling into a category of a “Fire Horse” according to TCM personality traits.
Although in these three sessions we focused treatment on her neck and shoulders, additional therapy might also focus on points around her right carpus and could also include laser therapy. Unfortunately, she is a black horse with black pigmented skin possibly limiting the depth of laser penetration (Duesterdieck-Zellmer, et al. 2016), however the scar tissue appeared to be directly under the skin and it would be a modality worth attempting.
References:
1) Pasteur CW. Effectiveness of acupuncture for treatment of cervical pain and stiffness in horses. Thesis. Chi Institute of Chinese Medicine, Reddick, FL.2017.
2) Stubbs, N. Clayton, H. 2008. Activate your Horse’s Core. Mason, MI: Sport Horse Publications. Pgs 15-18.
3) Duesterdieck-Zellmer KF, Larson MK, Plant TK, Sundholm-Tepper A, Payton ME. Ex vivo penetration of low-level laser light through equine skin and flexor tendons.2016.Amer J Vet Res 77(9):991- 999.