Claimant is a 37-year-old man who was working as a drywall installer for Employer on December 17, 2010, when he sustained an accidental injury arising out of and in the course and scope of his employment that resulted in injury to his left knee. The accidental injury occurred when Claimant was pushing a drywall cart that contained several sheets of drywall which he estimated to weigh 700 to 800 pounds. As he pushed the cart to make a turn, he pivoted on his left knee, felt a pop, and the knee buckled. Dr. L'Hommedieu performed a left knee arthroscopy, partial medial meniscectomy and excision of medial parapatellar plica on May 26, 2011. As Claimant's symptoms did not improve, Dr. L'Hommedieu performed another left knee arthroscopy and partial medial meniscectomy on September 29, 2011. Claimant was off work for about seven months, during which time he had physical therapy.
After the December 17, 2010 accident and continuing through the present, Claimant continues to experience pain, loss of motion, crepitus, swelling, and weakness in his left knee.
He experiences ongoing symptoms with movements including prolonged standing, stooping, squatting, kneeling, crawling, running, jumping, climbing and pivoting on his knee. He can squat to only about 85 % on the left side because of knee discomfort. Weather changes increase his left knee symptoms. He has difficulty performing yard work and house work. Mopping, sweeping, shoveling, carrying groceries and laundry up and down steps are all more difficult now. He has had to modify his approach to perform these tasks and paces himself now because he has no one else to do them for him. Claimant and Employer settled the workers' compensation claim arising out of the December 17, 2010 accident for 32.5 % of the left knee.
On April 2, 1999, Claimant was working construction and pivoted on his right knee with his right foot stuck in mud, injuring his right knee. Dr. Britt performed a right knee arthroscopic partial medial meniscectomy that repaired a severe complex tear of the posterior horn of the medial meniscus with both oblique and bucket handle and horizontal cleavage components. Claimant was off work for about three weeks. Claimant and his prior employer settled his workers' compensation claim arising out of the April 2, 1999 injury for 15 % of the right knee. Claimant testified that he didn't have any continuing complaints after his surgery and could do everything he could do before. He testified his knee was a little stiff from time to time, but not anything that hindered him from doing his job. He testified he had very little pain, but his right knee did not hinder him at all. He also testified his right knee did not hurt a lot more after he injured his left knee than it did before the primary injury.
On June 12, 2012, Dr. David Volarich examined Claimant, took a history, and issued a report. With respect to the primary work injury of December 17, 2010, Dr. Volarich diagnosed internal derangement left knee (bucket handle tear of the medial meniscus), status post arthroscopic partial medial meniscectomy and excision of plica, and recurrent left knee medial meniscus tear status post revision arthroscopy and partial medial meniscectomy. With respect to Claimant's preexisting injuries he diagnosed right knee internal derangement status post arthroscopic partial medial meniscectomy.
Dr. Volarich provided the following ratings of permanent partial disability, which he opined within a reasonable degree of medical certainty, combined to create a substantially greater disability than the simple sum or total of each separate injury, which constitute hindrances or obstacles to employment or re-employment, and for which a loading factor should be added. With respect to the primary injury of December 17, 2010, 40\% PPD of the left lower extremity rated at the knee; due to the torn medial meniscus that required two separate arthroscopic repairs, and account for ongoing discomfort, minor loss in motion, as well as crepitus and weakness in the left lower extremity. With respect to his preexisting injury, he found 15 % PPD of the right lower extremity rated at the knee, due to the torn medial meniscus that required arthroscopic partial medial meniscectomy in 1999, which accounts f